Matt Barkau's Free Icon To Speech is one of those projects you just really want to see succeed; it's a communication augmentation Activity for the XO that synthesizes speech in response to icon selections. If you're a new developer looking for some friendly code to play with, Matt's put in a lot of time to make it easy to work with - here's an example. If it looks like the kind of thing you'd like to help with, then check out the project's homepage and the rest of the code. There's plenty to work on both for developers and other contributors.
Also, since I don't believe I've plugged this here before: check out planet.sugarlabs.org if you want to keep up with the thoughts and work of the growing Sugar Labs community.
Finally, I've been growing slowly more interested in ASL and deaf culture (as may have been apparent from previous posts, including the ones where I've said things like this before). The grammar is particularly interesting; I'd love to take a class in ASL grammar specifically someday, never having formally studied it. I've taught several friends some of the tiny bits of ASL I know, but it often doesn't look right - we call it their "hearing accent" (I have one too). It's the tiny subtle things you do or don't do when you sign something - facial expressions, mouth morphemes, how far or fast your hands move, things like that - I dimly remember enough to tell it looks wrong somehow, but usually don't know enough to figure out how to make it look right again.
I want to live or work with other people who do ASL at some point; I need more frequent practice, and I'm at the point for that language where immersion would actually do me some good. (I'm not quite at that point for any other languages yet, but could probably get my Japanese and Mandarin there fairly quickly if given... say, a month's advance notice of such an opportunity.) When I look through the dictionary, I'm amazed at how quickly my vocabulary reactivates. I've seen a lot of these words before, I just... never signed them back at anyone. I wonder if learning my family's dialect would feel the same way. It's nearly impossible to find textbooks on that, though.