Free useful tools for web users

Tried to place this request in "Scrpts" but could not find a way to do that.
Must be doing or not doing something that stopped me posting there.
So even though scripts is I believe, the "best" section for my request, have no choice but to place it here.

So I would like to add free, interesting and useful tools for internet users, to a site aimed at the average web user.

Thanks a lot