well... there is always ssf... not really runescape style... and i guess not a true rpg..
theres no items involved, and its not a turn based game like rs
but no dl required <although flash 8 or more required>
and there is always ppl on u ken play with
once u reach lvl 80, u ken join a kingdom and kick the ases of other kingdoms
its kind of fun
there is like 3 classes, warrior, mage, and assasin
its a hk base server but its usually lag free
http://ssf.unrealize.com/ssf/news.php