Ok so there are more fun things to do out there. If you're the type of AutoHotkey programmer that doesn't like having to use the command prompt to write to an extra text file which your program has to read, then this is for you. DllCall will usually run contained in the program and can be hidden from the end-user.

The one to rule them all:
This is a function I pulled from the Autohotkey forums submitted by SKAN which lists all the functions for a specified Dynamic Link Library (DLL) along with an inputbox for convenience: 
InputBox, FunctionToDo, DLL File, Enter the name of the DLL file you want to (suffix with .dll):,,500,120,,,,,shell32.dll
If not ErrorLevel {
	ThisData:=PE_FunctionExports( FunctionToDo )
	IfExist, %A_Temp%\delete_me.txt
		FileDelete, %A_Temp%\delete_me.txt
	FileAppend, %ThisData%, %A_Temp%\delete_me.txt
	RunWait, %A_Temp%\delete_me.txt
}
PE_FunctionExports( PEFile ) {
	; Lists Exported Functions/ Comp@t: WIN32_NT +AHK +LA +LW
	;By SKAN www.autohotkey.com/forum/viewtopic.php?p=379086#379086 CD:20100824/LM:20100825

	VarSetCapacity( $LI,48,0 ), DllCall( "ImageHlp\MapAndLoad", A_IsUnicode ? "AStr" : "Str",PEFile, Int,0, UInt,&$LI, Int,1, Int,1 )
	nPtr := DllCall( "ImageHlp\ImageRvaToVa", UInt,Numget( $LI,12 ), UInt,Numget( $LI,08 ), UInt, NumGet( ( P := DllCall( "ImageHlp\ImageDirectoryEntryToData", UInt, NumGet( $LI,8 ), Int,0, UShort,0, UIntP,nSz )) + 12 ), UInt,0 )
	VarSetCapacity( Var,1024,0 ), VarSetCapacity( List,10240,0 )
	IfEqual,nPtr,0, Return SubStr( DllCall( "ImageHlp\UnMapAndLoad", UInt,&$LI ), 0,0 )
	Loop % NumGet( P+24 ) + 1
		A_IsUnicode ? Var := DllCall( "MulDiv", Int,nPtr, Int,1, Int,1, AStr ) : DllCall( "lstrcpy", Str,Var, UInt,nPtr ), nPtr := nPtr+StrLen( Var )+1,  List .= "`n" Var, A_Index=1 ? Omit := StrLen( Var )+2 : StringTrimLeft, List, List, %Omit%
	DllCall( "ImageHlp\UnMapAndLoad", UInt,&$LI )
	Return List
}
ExitApp


Examples of DllCall'ing:
// get number of network card interfaces
DllCall("iphlpapi\GetNumberOfInterfaces", "UintP", nIf)
MsgBox % nIf
...
// get current process ID
ProcessID := DllCall("GetCurrentProcessId")