Some data about size of Recent Changes and possible optimalizations.
RC (Polish, anonymous) for 250 articles has 198 720 bytes.
Some possible improvements:
* not generating space after <li> 249 bytes saved
* not generating newlines 356 bytes saved
* using <i> not <em> 319 bytes saved
* using <b> not <strong> 1219 bytes saved
* not generating </li> 1249 bytes saved
* not using class='internal'
(by making this default case) 4555 bytes saved
* not generating title="..." 7329 bytes saved
* using relative links for links to
http://pl.wikipedia.org/wiki/... 7713 bytes saved
* not generating PHPSESSID=... in links 9674 bytes saved
So:
* trivial markup changes - 2143 bytes, or 1.1% saved
* ... + making internal links default - 6698 bytes, or 3.4% saved
(this is trivial and doesn't affect anything)
* ... + relative links - 14411 bytes, or 7.3%
(still doesn't affect anything, but implementing generation of relative
links may be a bit tricky as we allow many different paths to
the same thing)
* doing all these changes except not generating </li> - 31414 bytes, or 15.8% saved
(it may have some minor effect on functionality)
* doing all these changes - 33047 bytes, or 16.6% saved
(won't be xhtml-compatible, but perfect html)