Firefox Extensions
At a recent meeting, the person sitting next to me groaned when the speaker said that our system was supporting Firefox as browser of choice. She leaned over and said that she didn't like Firefox at all and that it didn't have the same functionality she had in IE. While I don't agree about the functionality of the straight downloaded version, I did recommend that she look at extensions to help her customize Firefox.
PC Magazine now as a list of the Top 15 Firefox Extensions. I have others that I like even more, but this is a great jumping-off point for beginners at adding extensions.