Project Euler
A few days ago, I found a really great place, full of excellent math and programming problems: Project Euler.
Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.
I was long looking for this kind of place, to get my brain do some serious thinking :) It's a great way to improve logic and math/programming skills.
The problems can be solved by using any programming language, so as I just started learning Python, thought that this is a great way to start with it. As I suck more in math than in programming, my solutions are brute-forced, but I always go back to the explanation of the problem (can be viewed only after you gave the right answer to the problem), to understand the math behind the problem.
There are currently 214 problems and I'm on number 6 right now. If you into this kind of stuff, be sure to check it out, it's a lot of fun :)
Happy hacking!