Here are a couple of links that might help you out.
Obitus posted a great StJ and MA comparison. It has several atack chain calculations for StJ DPS. I recall SB-RC-HB-SB-CU-repeat as being the best ST chain but needs 300+% recharge in CU. Other chains that required significantly less recharge, the DPS was not much lower:
http://boards.coh.com/showthread.php?t=276359
Beber has created an app to calculate max DPS.
http://boards.cityofheroes.com/showthread.php?t=279838
I believe FM's best attack chain is Inc-Cre-GFS-repeat.
Ooo, thanks very much, I had no idea someone had created an app for it. 
Ok, I was wondering if someone could help me out, I need the optimal single target attack chains for fire, stj and titan weapons. I'm currently making (in some cases made) the stated and dark/kin scrappers so I can make my own comparisons for dps using similar builds. I will also be making brute versions of each however I will be just be using the scrapper builds on them so no gloom. Thanks for any replies
Alternitavely you could tell me how to work them out