Basic credits Trick:

in Windows 3.1 - 3.11 you can do this with any windows - native component (Program Manager, paintbrush, etc)

Hold down Shift + Ctrl  throughout the following steps:
 

• Click help - > about
• Double click the windows logo in the upper left corner. (nothing happens the first and every other times)
• Hit close and repeat.
• Various characters will appear.