Three more or less unrelated items of varying levels of interactivity:
Thomas Dietz juggling video #10. Even the people who I think are impressive jugglers think this guy is an impressive juggler.
You can skip the introductory section about time travel, which is the first quarter or so of the video; but once the juggling gets going, zowie. He starts out doing cool multi-ball stuff and multi-club stuff, with some great high throws and spinning around, and then he does a bunch of bits where friends toss him one or two balls or clubs while he's already juggling four to six items and he catches without looking and incorporates the new items into the pattern (including what someone later in the video refers to as the "double-blind ass catch"), and then there's a funny very brief attempt at poi, and then he goes on to stuff like juggling five or six clubs while standing on one foot.
Unfortunately, parts of the video are very dark on my Mac monitor (might be better on Windows, or Macs with gamma adjusted better), but the parts I can see are still really nice.
Warning: it's a 106MB file. But if you like juggling and you have a broadband connection, it's totally worth the wait.
You can also download a bunch of other Thomas Dietz videos, and the guy who put the video together also has a bunch of other juggling videos demonstrating various patterns in Siteswap notation. (But I haven't looked at any of the others yet.)
There's a new version of Tontie, the Flash-based "whack-a-mole on steroids" game. (To play it, click the "ver. 1" next to the hammer at the upper right of the Eyezmaze page.) Some parts of it have become lots easier, some lots harder. (Thanks, Lisa!)
At Just Letters, you can join dozens of other people who are simultaneously dragging virtual magnetic letters around on a virtual whiteboard. It's a fascinating exercise in cooperation and competition and limited resources and anonymous games and what people find interesting: some people try to drag all the letters into a big pile in a corner, others try to spell out swear words, others try to spell out "Merry Christmas." I joined at least one other user in trying to place the alphabet across the top edge, but other users appeared to be actively opposed to the idea. As I type this, there are 35 people simultaneously dragging letters; someone is collecting all the orange letters in a row down the right-hand side, and someone else is persistently gathering all the blue Ys in a row in the middle of the board, and someone else is spelling GOOGLE.
It might be fun to go there with half a dozen friends, all with the same prearranged goal, and try to impose your will; on the other hand, the anarchy of it and the fluidity of changing goals and changing levels of competition and cooperation is part of the fun. While I was helping with the alphabet, I was trying to take letters only from disorganized-looking piles of letters, to avoid the likelihood of getting in the way of someone else, but that didn't stop people from stealing my letters. I suspect that you have more of a chance of doing something relatively long-lasting if you focus on the less-used letters, but maybe not. (Thanks, Viva!)