Healcomputer - E-commerce technology site + computer related articles + product reviews.
Canned Emails - A minimal site with prewritten emails
IdiotBuy - Great list of awesome stuff to buy online.
analyze.email - Test the spam-y-ness of your emails
Awesome Stuff To Buy - Huge list of awesome stuff to buy online, if you're looking for cool things to buy this is for you, including gadgets and unique products from sites like Amazon.
Rename Email - Easily change the subject of any email, by cloudHQ