Free:
emacs for Windows
http://www.gnu.org/software/emacs/windows/ntemacs.html
For those that like emacs.
vim (vi)
http://www.vim.org/download.php
If you're hardcore old school.
Non-Free:
Visual Slickedit
http://www.slickedit.com/
A lot of hardcore professional devs I know swear by it. Has excellent source browsing and indexing features. Works great on huge projects (and I mean huge projects).
Source Insight
http://www.sourcedyn.com/
Best code browsing and syntax highlighting I've ever used. Fancier than Slickedit, but doesn't work quite as well on really big projects. A lot of hardcore professional devs I know swear by it. Smart Rename and the Relation window have saved me more time than I can remember.
Smart Rename is the coolest feature ever -- hit Ctrl-' and rename something, and the editor will figure out what references need to be changed throughout the project, taking into consideration scopes and classes. Ex: If you have Class1::Method1 and Class2::Method2, and you rename Class1::Method1, it will figure out it needs to also change every instance of pInstanceOfClass1->Method1(), but not pInstanceOfClass2->Method1().
Most editors do syntax highlighting, but Source Insight actually parses and understands the structure of the code: you can do things like browse the class heirarchy, references, and other cool stuff without ever having to compile anything.
Plus there's always Visual Studio. See if your school has a site license. It's got a decent programmer's editor built in.