My most dependable affiliate programs would have to be ShareASale, CodeCanyon, WP Engine and Postloop.

ShareASale:
- Offers a lot of tech and gadget sites, like Chinavasion, iSkin and heaps of different WordPress sites.

CodeCanyon:
- Amazing for Wordpress plug ins and themes. The affiliate network also spans across seven other really good premium web development sites.

WP Engine:
- Not only is this my favorite hosting service, but they also have a killer affiliate program with insane payouts of 150 dollars per referral. (If you do sign up, use my link and I will love you forever).

Postloop:
- A great site for forum owners and bloggers but they also offer an affiliate program that pays well.

I have been able to get somewhere with each of these. They are all legitimate programs and all of them offer PayPal payouts. They also work internationally. I am in Australia, so it can be a hassle finding decent programs. So these are the ones I have found and stuck by. I have provided links, so if you do sign up to any of these it would be great if you use my links. That way I can get some commission