I came across this site a year or so ago and really enjoyed using it to discover and draw various well-known fractals.

Here are a few programs I made with it. For some reason I tried to write them in a pure-ish functional style, accepting that the turtle has to move and turn but avoiding the "cheat" commands like setxy (placing the turtle at an absolute position) or make (setting a variable). Note that the default is to 'run normally'. You might want to click 'stop program' and then 'run fast'.

* Sierpinski triangle: http://logo.twentygototen.org/83EGZPPC

* Sierpinski carpet: http://logo.twentygototen.org/4c5iy9iU

* Sierpinski arrowhead curve: http://logo.twentygototen.org/hYDSZt8h

* Hilbert curve: http://logo.twentygototen.org/CFyUSzqG

* Hexaflake: http://logo.twentygototen.org/AJeuVkKc

this tree (found it on the 'recent' tab) is amazing: http://logo.twentygototen.org/CayQ5WNa

Here is the sieve of erastosthenes in logo:

http://logo.twentygototen.org/HxD0BYNH

And this is rather surprising

http://logo.twentygototen.org/PQD5ksVB

Wow. Just wow. Brought back memories from elementary school! I totally despised my computer class where we were taught logo. During the exam I walked in completely clueless. Not knowing anything and having tonnes of time in front of the screen, I started typing some commonsense words and numbers and BOOM! stuff started showing up on my screen. I passed the exam--thanks for the geniuses who made a truly simple language an idiot kid could figure out!

I used it before I knew it was a programming language. I got it in a game disk and it came with a "cheatsheet". I learned the combinations in a few minutes and had it drawing things. Pretty soon, 2-3 days, I grabbed a math book to lookup formulas :-)

in my primary school classes, we were lucky enough to have one of the logo turtle robots. Special memories..

Brought back memories to me as well but I loved my computer class! It wasn't really a computer class, it was more like sit in front of computers and here are some books. This was in grade 2 for me, using Comterm MAX computers.

It is available on google code: http://code.google.com/p/papert

It is also in some serious need of attention after being plagued by spambots.

If anyone fancies hacking on it I will happily add them to the svn repository/google app engine.

Hey Thomas, I was gonna volunteer to add a few mathematical routines, I needed ABS and RANDOM to play with it, but I got the sources and found out they're in there, just not documented :-)

Interested parties can read logo.js; search the file for addCommand, addTurtleCommand, addPrimitive, addInfix, etc.

I see you have s-exp parsing in your TODO list, perhaps I can take that for a task. Along with some documentation. Otherwise it looks great :-)

I've added the email in your profile to the project

This is depressing. I spent the last 3 nights working on this same idea, except it was closer to Python's turtle module than Logo, and it used Google's Closure library.

Oh well, I'll continue on.

Well, I'm sure you could help out the project instead of building another one, or you could just continue on :)

It seems like I've run across a couple implementations of Logo in javascript recently. Here's another:

http://www.calormen.com/Logo/

And, here's one that uses svg instead of canvas:

http://www.amberfrog.com/logo/

I think it'd be a lot of fun to do webapp for creating and sharing artwork made in Logo -- with a bunch of github-like social features. Or, maybe Facebook integration?

Logo was my favorite thing about 4th and 5th grade, and I've not touched Logo code since then. Having not touched it in the 25-odd intervening years, my memories of struggling to hold a whole program design in my head are relatively clear; and it is amazing how much easier programming is now. Something to remember if my kids start wanting me to teach them to program a couple of years from now.