I use ThinkorSwim. Just switched over from Etrade about a month ago. So far ive been pretty happy, take some time getting used to. I have to use the web based app mostly since cant use the software from work, but its well organized and has good option layout. I like it better than etrade. I can do forex, commodities, options and equities pretty much from the same account really easily and fairly cheaply. Downisde is the customer service, they are real nice but when I call I feel like they are short staffed. I get the answering machine fairly often.
They also send you a monkey in the mail (stuffed one of course)