I discovered Associated Content via a forum on Suite 101.  I love it!  You pick your own content.  You can then submit your material for an upfront payment AND still get performance payment. 

I have submitted three articles thus far (2 in history and 1 in health) and have been given an upfront payment for them all.  Best of all, as soon as you accept the offer, they send payment right away.  No waiting to make a $25 minimum before they send payment.  And on performance pay, there is only a minimum of $1.50 to receive your money.  Performance pay is only sent monthly, however. 

Note to everyone: I am NOT getting paid if you sign up for Associated Content.  They do NOT pay for referrals.
Note #2: They do check every article for proper grammar, spelling, etc.  I have not had one kicked back yet (but I've written lots of articles), but it is mentioned in the forums.  I will be doing an article within a few days on tips for writing great articles.