AppBrain is one of the best market explorers available. With it you can browse the market via the typical top apps of the different categories either from your desktop AppBrain.com or from your phone. Along with that, when bringing up an app on your desktop, AppBrain will show you related apps that you may find interesting or even find better than the app you're currently checking out. AppBrain also has the ability to sync app lists between your phone and the site allowing you to queue up multiple installs/uninstalls. Simply bring up the Manage Apps and click the sync button. Your first run will ask if you'd like to signup with your google account which makes the entire sign up process painless. After a quick sync on your phone, the app can automate your install/uninstalls you've set up from the website, which quite frankly is a godsend for anyone not running Froyo yet.