Muitas vezes precisamos salvar um arquivo ( como o de configuração da app ) em disco e gostaríamos que esse arquivo ficasse na mesma pasta ou numa pasta irmã da aplicação corrente.
Através das variáveis de ambiente temos acesso ao nome de pastas de sistema bem como da aplicação e da configuração do equipamento como qual a versão do Framework, quantos processadores, memória etc.

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Linq

Module Ambiente
    Public Function Ambiente() As List(Of String)
        Dim a As New List(Of String)

Discos no sistema - drivers de disco

        a.Clear()         a.Add("Discos : ")
        For Each drive As String In Environment.GetLogicalDrives()
            a.Add(" Drive : " + drive)
            a.Add(" ")
        Next

Versão do sistema operacional

        a.Add("OS : " + Environment.OSVersion.ToString)

Número de processadores

        a.Add("Número de Processadores : " + Environment.ProcessorCount)

Versão do framework .NET

        a.Add("Versão .NET : " + Environment.Version.ToString)

Exibe ou define o código de término do programa

        Environment.ExitCode = 0 'sucesso
        Environment.ExitCode = -1 'falha

nome da maquina

        a.Add("Nome da máquina : " + Environment.MachineName)

Pilha do aplicativo

        a.Add("Pilha do aplicativo : " + Environment.StackTrace)

Diretório do sistema

        a.Add("Diretório do sistema : " + Environment.SystemDirectory)

Nova Linha

        a.Add("Nova Linha : " + Environment.NewLine)

nome do usuário logado

        a.Add("nome do usuário logado : " + Environment.UserName)

dominio

        a.Add("nome do usuário logado : " + Environment.UserDomainName)

diretório corrente

        a.Add("nome do usuário logado : " + Environment.CurrentDirectory)

pasta default do usuário

        a.Add("Pasta default do usuário : " + Environment.GetFolderPath(0))

Sistema operacional de 64 bits ?

        a.Add("Sistema operacional de 64 bits ? : " + Environment.Is64BitOperatingSystem)

O proccesso é de 64 bits

        a.Add("O processo é de 64 bits ? : " + Environment.Is64BitProcess)

Pastas especiais

        a.Add("Pastas especiais ")
        a.Add(" AdminTools:" + Environment.SpecialFolder.AdminTools)
        a.Add(" ApplicationData:" + Environment.SpecialFolder.ApplicationData)
        a.Add(" CDBurning:" + Environment.SpecialFolder.CDBurning)
        a.Add(" CommonAdminTools:" + Environment.SpecialFolder.CommonAdminTools)
        a.Add(" CommonDesktopDirectory:" + Environment.SpecialFolder.CommonDesktopDirectory)
        a.Add(" CommonDocuments:" + Environment.SpecialFolder.CommonDocuments)
        a.Add(" CommonMusic:" + Environment.SpecialFolder.CommonMusic)
        a.Add(" CommonOemLinks:" + Environment.SpecialFolder.CommonOemLinks)
        a.Add(" CommonPictures:" + Environment.SpecialFolder.CommonPictures)
        a.Add(" CommonProgramFiles:" + Environment.SpecialFolder.CommonProgramFiles)
        a.Add(" CommonProgramFilesX86:" + Environment.SpecialFolder.CommonProgramFilesX86)
        a.Add(" CommonPrograms:" + Environment.SpecialFolder.CommonPrograms)
        a.Add(" CommonStartMenu:" + Environment.SpecialFolder.CommonStartMenu)
        a.Add(" CommonStartup:" + Environment.SpecialFolder.CommonStartup)
        a.Add(" CommonTemplates:" + Environment.SpecialFolder.CommonTemplates)
        a.Add(" CommonVideos:" + Environment.SpecialFolder.CommonVideos)
        a.Add(" Cookies:" + Environment.SpecialFolder.Cookies)
        a.Add(" Desktop:" + Environment.SpecialFolder.Desktop)
        a.Add(" DesktopDirectory:" + Environment.SpecialFolder.DesktopDirectory)
        a.Add(" Favorites:" + Environment.SpecialFolder.Favorites)
        a.Add(" Fonts:" + Environment.SpecialFolder.Fonts)
        a.Add(" History:" + Environment.SpecialFolder.History)
        a.Add(" InternetCache:" + Environment.SpecialFolder.InternetCache)
        a.Add(" LocalApplicationData:" + Environment.SpecialFolder.LocalApplicationData)
        a.Add(" LocalizedResources:" + Environment.SpecialFolder.LocalizedResources)
        a.Add(" MyComputer:" + Environment.SpecialFolder.MyComputer)
        a.Add(" MyDocuments:" + Environment.SpecialFolder.MyDocuments)
        a.Add(" MyMusic:" + Environment.SpecialFolder.MyMusic)
        a.Add(" MyPictures:" + Environment.SpecialFolder.MyPictures)
        a.Add(" MyVideos:" + Environment.SpecialFolder.MyVideos)
        a.Add(" NetworkShortcuts:" + Environment.SpecialFolder.NetworkShortcuts)
        a.Add(" Personal:" + Environment.SpecialFolder.Personal)
        a.Add(" PrinterShortcuts:" + Environment.SpecialFolder.PrinterShortcuts)
        a.Add(" ProgramFiles:" + Environment.SpecialFolder.ProgramFiles)
        a.Add(" ProgramFilesX86:" + Environment.SpecialFolder.ProgramFilesX86)
        a.Add(" Programs:" + Environment.SpecialFolder.Programs)
        a.Add(" Recent:" + Environment.SpecialFolder.Recent)
        a.Add(" Resources:" + Environment.SpecialFolder.Resources)
        a.Add(" SendTo:" + Environment.SpecialFolder.SendTo)
        a.Add(" StartMenu:" + Environment.SpecialFolder.StartMenu)
        a.Add(" Startup:" + Environment.SpecialFolder.Startup)
        a.Add(" System:" + Environment.SpecialFolder.System)
        a.Add(" SystemX86:" + Environment.SpecialFolder.SystemX86)
        a.Add(" Templates:" + Environment.SpecialFolder.Templates)
        a.Add(" UserProfile:" + Environment.SpecialFolder.UserProfile)
        a.Add(" Windows:" + Environment.SpecialFolder.Windows)


        a.Add(Environment.CurrentDirectory)
        a.Add(Environment.GetFolderPath("Desktop"))

        a.Add(Environment.SpecialFolder.AdminTools)
        a.Add(Environment.SpecialFolder.ApplicationData)
        a.Add(Environment.SpecialFolder.CDBurning)
        a.Add(Environment.SpecialFolder.CommonAdminTools)
        a.Add(Environment.SpecialFolder.CommonApplicationData)
        a.Add(Environment.SpecialFolder.CommonDesktopDirectory)
        a.Add(Environment.SpecialFolder.CommonDocuments)
        a.Add(Environment.SpecialFolder.CommonMusic)
        a.Add(Environment.SpecialFolder.CommonOemLinks)
        a.Add(Environment.SpecialFolder.CommonPictures)
        a.Add(Environment.SpecialFolder.CommonProgramFiles)
        a.Add(Environment.SpecialFolder.CommonProgramFilesX86)
        a.Add(Environment.SpecialFolder.CommonPrograms)
        a.Add(Environment.SpecialFolder.CommonStartMenu)
        a.Add(Environment.SpecialFolder.CommonStartup)
        a.Add(Environment.SpecialFolder.CommonTemplates)
        a.Add(Environment.SpecialFolder.CommonVideos)
        a.Add(Environment.SpecialFolder.Cookies)
        a.Add(Environment.SpecialFolder.Desktop)
        a.Add(Environment.SpecialFolder.DesktopDirectory)
        a.Add(Environment.SpecialFolder.Favorites)
        a.Add(Environment.SpecialFolder.Fonts)
        a.Add(Environment.SpecialFolder.History)
        a.Add(Environment.SpecialFolder.InternetCache)
        a.Add(Environment.SpecialFolder.LocalApplicationData)
        a.Add(Environment.SpecialFolder.LocalizedResources)
        a.Add(Environment.SpecialFolder.MyComputer)
        a.Add(Environment.SpecialFolder.MyDocuments)
        a.Add(Environment.SpecialFolder.MyMusic)
        a.Add(Environment.SpecialFolder.MyPictures)
        a.Add(Environment.SpecialFolder.MyVideos)
        a.Add(Environment.SpecialFolder.NetworkShortcuts)
        a.Add(Environment.SpecialFolder.Personal)
        a.Add(Environment.SpecialFolder.PrinterShortcuts)
        a.Add(Environment.SpecialFolder.ProgramFiles)
        a.Add(Environment.SpecialFolder.ProgramFilesX86)
        a.Add(Environment.SpecialFolder.Programs)
        a.Add(Environment.SpecialFolder.Recent)
        a.Add(Environment.SpecialFolder.Resources)
        a.Add(Environment.SpecialFolder.SendTo)
        a.Add(Environment.SpecialFolder.StartMenu)
        a.Add(Environment.SpecialFolder.Startup)
        a.Add(Environment.SpecialFolder.System)
        a.Add(Environment.SpecialFolder.SystemX86)
        a.Add(Environment.SpecialFolder.Templates)
        a.Add(Environment.SpecialFolder.UserProfile)
        a.Add(Environment.SpecialFolder.Windows)

        a.Add(Environment.SystemDirectory())

        a.Add(Environment.GetFolderPath(Environment.SpecialFolder.Desktop))




        Return a

    End Function
End Module