I want to know if it is even possible to jump my cursor from left/right of every typed word using Vimperator, a Firefox addon that behaves like Vim, including its shortcut keys.

So a good example would be:

I took a marvelous dump right before bed and I so happen to sleep better.-

Now if my cursor is at the end of that sentence (hence the dash) how can I jump my cursor right before the word better by just using a shortcut key?

by default Ctrl+A & Ctrl+E are shortcut keys that brings your cursor to beginning/end of the current line your on.