@evil_nerd
There is one program I definitely can remember called "WBStripes" or something, that made gradient stripes on you workbench backgound - it definitely worked with WB1.3 There are a few other eye candy things I've got around somewhere, like "Exploding Windows", which made windows do a little zoom effect when they opened or closed - hardly a subtle effect though :-D Reply/Pmail/Email me if you want me to have a dig around for them.
So with this program it would be possible to do something like a Boing Ball or something to? Anybody knows the name of this app? :-)
If it's how I remember it worked (that's a big "if") you could possibly have a simple boing-ball. Remember though that that would use up two of your available pens - two colours from icons, windows, WB apps etc would have to be red and white (probably not too bad if you changed the orange to red, maybe?)
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BTW I've no idea if both programs could run together (could be a nice effect if they did!) And I'd agree with other people that you
really need to upgrade to do anything serious, even if that's just serious eye-candy :-P