1. over-bloated alternates, which work in bizarrely unexpected ways. fine they use their own rendering engines, but get the UI working right already.
2. skinned versions of the stock browser, most of which BREAK the UI.
3. iPhone Safari knock offs. or at least trying to be, as not one of them acts properly.
4. cheaply made garbage, thrown together to try to leech a buck or 2 out of us. need i elaborate?