are there any web browsers out there with full support for javascript, and can render html normally? I wouldn't need anything like flash or java applets, but full support for fancy javascript would be nice for getting through fancy web sites and such. If one doesn't exist, I think I might try to make one, and shoot for 5 - 15MB of ram usage.
That would be convenient for a copying collector. It might be better to use a generational collector, and when you garbage collect and find that you no longer have enough memory for the live set, allocate a new generation.
There is also mark and sweep style, which can be nice since you don't need to copy memory around. You do need to sweep through the entire heap to free the unreachable objects though, rather than just the live set. Here is lua's implementation: