When asked about his setup:
What does your setup contain?
It’s a computer—a Mac, and [Apple Logic Pro 9], samples, and headphones.
Do you also use Logic in the studio when you’re doing the big sessions, or is it Digidesign Pro Tools?
No, only Logic.
Only Logic. According to the interview, he and Gaga wrote “Bad Romance” on the tour bus with this setup. You don’t need lots of gear, you just need to know how to use it.
Obviously, the rest of the interview is required reading.