Not a joke. Here's something I posted in a recent thread to disable/enable CSS in web pages with the s / shift-S key (perhaps because CSS makes a particular website worse).

    nmap s :emenu View.Page Style.No Style<CR>
    nmap <S-s> :emenu View.Page Style.Basic Page Style<CR>

You could assign the 'b' character to the :back command, or use the default shift-H. If you want to go back 4 pages, you can simply type "4 o", just like in vim.

You can. I used to be a Vimperator user few years ago. Left because I felt it made browser a bit slow.

yes, you can definitely do that. I'm using the chrome version (vimium) but have back mapped to capital h (for history)