Something I've been wanting to do for a good while now. I'd like to bring your attention to this nifty addon which allows you to enable/disable addons without relogging.

http://www.wowace.com/projects/acp/

It can save profiles and can be stored by class. Example for me would be a profile for raids with almost everything disabled and one for solo play which loads addons like gathermate or auctioneer. Especially handy when an addon needs to be loaded and relogging would take too long (patchdays).

This is just a copy of the old cosmos add on.
However I am using it from at least 8 months, that is from when they have stopped upgrading cosmos. it is very useful if you have many add on
Every char can save various set of add on, never tried to share the set betwen the char.