I'm going to resurrect this thread to weigh in against Hungarian – or at least the version of it that's commonly used. The prefix letters make it much harder to read the word (which actually tells you what the variable does) at a glance, because the eye 'picks' words by looking at the beginning, the end and the shape. By slapping some nonsense letters on the front, any prefix (or indeed suffix, although less so) convention makes it hard to read.
There's also the issue of what happens when a variable changes type, which while not common is certainly not unheard of (int to long or int to double happens quite often).
The 'wordy' part of the name should tell you the purpose, so you don't need a prefix to do that. And I agree that if you don't know where to find the declaration, you've no business changing the code until you understand it more (plus, modern IDEs will tell you what type a variable is and where it's declared).