A prime example of this is Shaun Goater. Once he found his feet I knew he could probably do better than us, but never thought I'd be watching him on MOTD scoring hat tricks in the Premier League.
Another one is Clive Mendonca. Decent player for us but I was surprised to see him playing and scoring for Charlton in the Prem.
Kari Arnason .Already a good player when we got him but showed how good he was in the Euros and WC.
Dave Watson? He was a good player for us but not sure if anyone ever expected he might go on (career wise) to possibly be the best ever Miller. FA Cup winner with Sunderland and went on to play many years at Man City. Also, I believe he is still the most capped England player to never play in a World Cup Finals.
Alan Lee an injured overweight footballer that couldn't get reserve team football before he came to us.
Lewis Grabban?
Stuart Talbot, a crock after a bad leg break. He was a monster for us.
Mendonca was worshipped by Charlton fans and it was well deserved too. Clive never had a big time charley attitude and was a nice fella who was happy to sit and talk football with anyone who wanted too.