Mozilla Firefox has officially released pre-Alpha build of Fennec that would atleast work on Motorola Droid and Google Nexus One. Note that this is only a pre-Alpha build of the browser for testing purposes.
Fennec Browser for Android
Being Pre-alpha release, Fennec for Android is really buggy and only works with Android 2.0 though it does support extensions. You might want to read below warnings before proceeding for Fennec Pre-alpha published by Vladimir.
1. We’ve only really tested this on the Motorola Droid and the Nexus One.
2. It will likely not eat your phone, but bugs might cause your phone to stop responding, requiring a reboot.
3. Memory usage of this build isn’t great — in many ways it’s a debug build, and we haven’t really done a lot of optimization yet. This could cause some problems with large pages, especially on low memory devices like the Droid.
4. You’ll see the app exit and relaunch on first start, as well as on add-on installs; this is a quirk of our install process, and we’re working to get rid of it.
5. You can’t open links from other apps using Fennec; we should have this for the next build.
6. This build requires Android 2.0 or above, and likely an OpenGL ES 2.0 capable device
To get this pre-Alpha build of Fennec browser, you can point your phone browser to bit.ly/fennec-android (Direct APK Download Link). Before installing it, make sure to make your settings to allow you to install non-market apps. To make sure goto Settings-> Application-> and check “Unknown Sources”.