Besides my own products, I promote other people's products as an affiliate. Although there are some scripts around, many of them do not have link cloaking capabilities included, which is fundamental to protect your affiliate links from others that will steal your commission by replacing your affiliate ID with their own. Yes, as ugly as it sounds, it does happen. In fact, a few days ago I saw a presentation by a guy who created a program to do just that. I think he calls it carbon copy or something of the sort. He was very proud of it and saw nothing unethical about it. I beg to differ.
Anyway, my idea is that one's affiliate link would be "cloaked" or "mapped" to a real URL (not that bitly or whatever thingy) in WordPress, which one customizes (so it is unique) and the actual affiliate link is either encrypted or hidden somehow from the customer's view and would-be thieves.
The solutions available that I have found in WordPress.org repository provide you with a "fake" store that when the customer clicks on the item, it takes him or her to merchant's site (e.g., Amazon) and leaves you exposed. Not good! Besides, who has the time to create "cloaking" php pages for every merchant or product (especially if one has many) or point the affiliate link to one's domain via the domain manager? A few products, perhaps....
Anyway, it's just an idea to produce something much better than just ridiculous short URLS that do not provide much confidence to the customer. I usually don't click those links and I know many who don't either because they look "suspicious".
Thanks for your time and for considering this idea and making it even better, if you decide to give it a "go".