jsMath
jsMath itself is working, see:
http://www.server-sky.com/jsmathdir/test/index-images.html
http://www.server-sky.com/jsmathdir/test/index.html
http://www.launchloop.com/jsmathdir/test/index-images.html
http://www.launchloop.com/jsmathdir/test/index.html
moin-moin jsMath is only partly working (Friday July 10 2009 10am PDT)
see http://wiki.themel.com/PublicTestPage
Here are some math equations using those markers. Some inline math: 1−x2
\int {1\over x}\,dx = \ln(x)+C
and
\[\sum_{i=1}^n i = {n(n+1)\over 2}.\]