I adored my spirograph when I was a kid, so I went looking for some online versions of the game and came up with quite a few. My favorite is a Flash version from Myers Design because it offers a nice, clear image in case you want to make a screen shot, plus it allows you to choose your own hexadecimal color, switch the background from black to white, and adjust other parameters, including line size. I also really enjoyed the spirograph demo in the very fun "Flash Bestiary" from "krazydad". If you are a bit of a spiro-nut, keep walking this way, and check out these different Java spirograph applets: one with many parameters, that you are free to use on your site if you'd like (from the creator of the Internet Anagram Server); another nice one that gives lots of explanation and also allows you to download the applet; and this one that also has a fun "random" button for hypno-clicky goodness.
Also go marvel at this teeny-tiny (1167 bytes) spirograph pattern generator from a past 5K contest entry (description here), and visit SpiroRama for a software spirograph you can download to use on your computer (or just have fun looking at some screenshots). You may also want to take a peek at this example of actual artwork created using spirograph, and finally, just in case you ever wondered if you really are going around in circles all the time, take the "What childhood toy from the 80s are you?" quiz to see if you qualify as a Spirograph!
I always have the semi-serious feeling that there are ghosts and angels in my computer, because no matter what strange whimsy may overtake me, without looking for it I will come across a related something-something within a matter of hours, and if I've just acquired a brand new piece of information that has managed to evade me for four decades, I'll suddenly see five more references to that same formerly elusive bit of something within the next day. Well, today I had a somewhat similar experience: First I discovered Chank's free font archive, where I downloaded all the "twiggy" fonts, and then spent quite a few minutes contemplating the rather amazing Cowboy Rhumbahut. Then, several hours later (via quite a long and meandering path) I found myself at the home of an interesting experiment called Synesthetic Bubble Gum Cards (which I love, though I don't quite have it figured out yet), where something kept nagging me about the front page, until I realized... Yup. Cowboy Rhumbahut. Now just what are the chances of running into a Cowboy Rhumbahut twice in the same day?
PS: I've posted a new set of pretty sweet little patterns I'm calling "Lullaby".
I had bookmarked the Project Lite Moire Phenomena site some time ago, but was frustrated to find that the Bush necktie debacle brought it into the glare of the blogging world before I could gather the other links that I wanted to include with it. Here are a couple of nice ones: Molecular Expressions' Moiré Pattern Generator, which we've visited before, and their fun page of moiré-fueled movement illusions, and permadi.com's animated moire circles and moire fractal pattern generator. More, more moiré at Sandot Science, Mathematik, and Eluzions.
For some nice moiré-style tile backgrounds, see these "silk moire" patterns from my old Tile-a-Day.
Just a quick note to say that I uploaded a new set of tiles yesterday - a nice group with a sort of low-key Op Art pattern (well, low-key for Op, anyway!). These are designed especially for you to colorize (though I actually like them a lot in their neutral state), and I've also created a set of OverAlls out of the larger tiles for those of you who like to skin your sites, or if you just want to change background colors without changing patterns.
And while we're on the subject of Op, as in "Optical", let me recommend (for the more daring among you) Akiyoshi Kitaoka's tricky wallpaper, because you have to love desktop designs that come with the warning, "might make you feel sick". See a whole lot more eye-defying feats on the rest of his illusion pages. By the way, I love his idea of "Illusion therapy" - I just might have to steal that, and do some "tile therapy". I mean, check out his "Muscarinergic therapy" (third from bottom), and my third tile on this page. Now doesn't that activate your depressed mind?