app brain see's what apps are on the phone or the list you make from the web site and makes recommendations based on it, it also has hot list of what is being downloaded the most, its basically social networking for the android market, also the website on the side has list of similar apps your viewing and list of other apps wrote by same person, the appbrain app will sync your computer list of apps to the phone
its really great way to stumble threw the massive amount of apps, someone in podcast said 300 apps are being added a day, i dont know how accorate that is but i dont have time to go threw anything close to 300 apps, lol
it works better linked to your gmail account but it is browse-able without
i :heart: appbrain
Edit: opps, forgot the downside... you might get addicted to downloading great apps