Keyword tag cloud

[chadon]

I have found a very interesting function in the forum at http://wordpress.org/tags/ that allows users to enter keywords with their post and display them with a link to that keyword(s) search result in each posts. This function would be very interesting for busy forums and would help users and search engines to find specific posts. I don't know how this can be done but it doesn't seem hard to make a mod for that.
Post with tags on the right:
http://wordpress.org/support/topic/78678
List of tags:
http://wordpress.org/tags/

[Neol]

This is very interesting.

[vbgamer45]

I am working on this mod.

[Neol]

I am working on this mod.

A really good news

Cheers.

[franklinrony]

I am working on this mod.

marvelous wait the mod.greats

[JayBachatero]

Tagging System For Topics