Silliness page 2
As well as being the bane of our lives, computers do also offer us plenty of opportunities for fun and games. And larking about.
In both Mulberry and an earlier version of REALbasic, it was possible to open as many about boxes as you wanted:

Windows is of course an endless source of ways to lark about, including messing about with its useless window mangler:
Scribble 2000 is a Graffiti™-like handwriting recognition program for EPOC devices. What the developer did not foresee was a clown like me drawing a letter of infinite length until the program fell apart.

If you are lucky, a computer will even tell you that you are silly. I suspect that they should do this more often.

The updated BBC BASIC V for the Acorn Archimedes range still features this delightful error; see for yourself.
On a lagged PC or if you have lightning-fast fingers, it is possible to open two instances of the Windows Date/Time control panel via the system tray:

With judicious use of the control key and clicking – intended for selecting multiple taskbar items – you can have the taskbar not indicate show the active program (although I find that it tends to do this by itself), or have a program active even with a multiple selection: