One of my 2009 resolutions is to solve 2 ACM problems per month. I haven't done that since 2005! The UVa Online Judge offers a wide selection of problems. you can submit your solution in "C, C++, Java, or PASCAL". From my experience => Java is slow, C is hard (String is an array of chars!), C++ was the best, and I don't know PASCAL! I will give Java another shot if not, I'll stick with C++.
I have selected two random problems with high success rates.
10015 - Joseph's Cousin
10019 - Funny Encryption Method
Any one interested? :p