I've been spending a bit of time going through this site lately.
It's got a bunch of comic-book based urban legends - which have recently been collected into book format as 'Was Superman a Spy?: And Other Comic Book Legends Revealed!' by Brian Cronin. It's been a fun read - I've been on the fringes of what's been going on in comics in the last decade or so, so I've missed a bit, but it's still a good read. I highly recommend taking a look to see if any catch your eye.
The other good site that my kids are enjoying is Marvel's Create your own hero site - which has a bunch of templates you can use and color to create a super hero. It's also a good way to kill an afternoon.