Clarify the kind of math. Opportunities differ wildly based on that.

In the meantime, here's a quick breadth-first laundry list of possibilities, in no particular order.

1. Statistics and probability: analytics and finance
2. Geometry, topology: 3D printing, game programming, FX/CGI
3. Linear algebra, matrix theory: computer animation, graphics, optimization work in logistics-driven companies, general purpose modeling
4. Number theory: security, cryptography/NSA if you are actually any good at it, "fries with that" otherwise.
5. Logic and foundations: AI, NLP, semantic web technology, Wolfram
6. Analysis: you want fries with that? (or: pick up some control theory and numerical computation skills and look in traditional big company engineering in areas like control design, signal processing...)
7. Ridiculously advanced algebra, category theory, stuff like that: assistant to people who ask "you want fries with that?" (heh heh, just my little dig at Sridhar Ramesh). Their time will come. The functor will inherit the earth.