I have seen the 2-Pointers method being used in some problems. For example, it was used in the recent Codeforces contest in problem D: http://www.codeforces.com/contest/190/problem/D. I found the solution very interesting.
Also, in my TopCoder post http://apps.topcoder.com/forums/?module=Thread&threadID=733641&start=0&mc=6#1480079, AzizKhan gave a very nice solution using 2 pointers.
Can someone point me to more similar problems so that I can practice this approach? Thanks in advance!