Discworld

I have read:
-The colour Magic
-The Light Fantastic
-Sourcery
-Troll Bridge
-Equal Rites

So what Discworld book should I read next?  Should I keep with the Rincewind novels, read the next in the Witches novels, or read something else?  I plan on reading all the books in time but I want to read them in the best order possible so help me out.

>>9
You never get to think much while reading Pratchett's books. They're just random collections of anectodes stuck in messy parodies anyway.