i used to play a load of iron maiden stuff when i was learning to use my 3rd finger for picking, but i found it was only really useful for 'gallop' style rhythms - for more expressive use of the technique try some jaco stuff (eg. 'come on, come over') - even if you aren't a fan of the music it'll get you into string skipping and more in-depth applications.
then chuck your thumb into the mix
[url="http://www.youtube.com/watch?v=rW0Hoxo32FA"]http://www.youtube.com/watch?v=rW0Hoxo32FA[/url]