I think it depends in your CMS you are using, there are compoents to make friendly URLs , but they must match the platform you are using
You can use web-server features: .htaccess and mod_rewrite
i use mod_rewrite but i need more search engine friendky pages without
Something about cloaking the url. If you don't do it right google will consider that you are trying to spam the search engine and ban your site from their directories. Study about it carefully before doing it.
You can try bring2u.com !
However, as like the above mentioned, google is not favor in
cloaking. You can use it for yourself.
Why can't you use mod_rewrite?