Is tag clouds useful ?

This is one of the most common question in most of the webmaster now a days.
Tag clouds may be good or no effect if they are used in limited numbers but if they are stuffed excessively then they are really bad for the site and google may penal you site.

here is a video by a google employee, watch this.





So be careful about using tag clouds.

My experience : It has penalized one of my site and my ranking gone down by 200%
The keywords used it was just 12, yet my site got a hit and now I have removed it and its getting back to normal.