John Terry comes first on my list after his new contract.
I used to put Riquelme on this list but kudos to him he's impressed me so much I actually think he's underrated now.
Canavaro- How he won the FIFA world player of the year is beyond my comprehension. He was pretty good in world cup, but that's about it. wasn't outstanding. I agree we don't give defenders enough credit, but you have to give credit when its due.
frizzyan, EF has a "Search" feature that you can use to find existing topics! It's pretty cool. If you look on the right side of your screen, you will see a list of things such as "My Community" and "Videos". Well, there is also one there called "Search". Click on that one and search Overrated/Underrated and you should find the existing topic.
If you have any difficulty using the "Search" feature, feel free to PM me.