(reverse-i-search) in Bash

Actually, another answer to that question gives a better option.

In your ~/.bashrc add the following line:

stty -ixon

Then you can use Ctrl-s to step forward through the history in the same way as you would use Ctrl-r to step backward.

This will even work to start a new forward search (called i-search as opposed to reverse-i-search) while browsing through history. Suppose you do Ctrl-r and type some text of a command near your destination then press up arrow several times overshooting what you were really looking for (or you change your mind). Now press Ctrl-s and type a few characters from that line. Zoooom! Straight to it.

There's a similar question on stackoverflow.com.

The best answer there is to use Ctrl+G to cancel the current search.