[Maro]

Disclaimer: I have a degrees in both CS and Physics.

If you learn C/C++ programming, you'll be able to get a job at an investment bank and won't have to worry about money. If that's something that attracts you, study (and write code) in a field where Monte Carlo simulations are used, like lattice gauge theory, which is a lot of fun and will help you understand QFTs. Here's some links to get started:

http://latticeguy.net/mypubs/pubs.html

Some C code:

http://thy.phy.bnl.gov/~creutz/z2/

If you want to do something like a web startup and learn Ruby on Rails, then Physics won't help you much. You'll just be on equal footing with CS guys, if you put in the time.

PS: Most physicist I know are absolutely terrible software engineers. If you're going to write larger programs, please read some books about how to write larger programs!