speedr.js: Spreeder [1] in 492 chars (via @fogus).

Turns out there actually is a bookmark [2], but mine is likely shorter, has
less features and no facebook comments below it. And it destroys the
site your on. Those are all features.

Now try getting this thing smaller!

[1]: http://www.spreeder.com
[2]: http://www.spreeder.com/bookmarklet.php
Shorter (425 chars, worse variable names).
Even shorter (406 chars, inlined q selector).
Less. (340 chars, s/createElement/innerHTML/)
Even less. (332c, don't need no closing tags)
Smaller. (326c, who needs semicolons?)
Tinier! (318c, all hail the global var)

I could have been nasty and redefined a, but well, it's about reusable
code, isn't it?
Significantly tinyier. (161c, functions obsoleted)

It's interesting to see that my abstractions from the beginning
(qa=document.querySelectorAll,ary=array conversion) aren't even used
anymore. And still I think they helped me think reasonably about this
thing, without them I'd probably not yet be here.

Interesting things. And almost a tweet, need to shave off 21 chars,
though.
More tiny. (159 chars, hello C)

If I'd take out the font-size, it would be tweetable.
Smallish (152c, bye window.)
Y' know. (148c, inlined n aka nextWord)
There's more. (145c, ternary if)
Tweetable! (140c, aliased body instead of document)