I've been very successful in just sliding a small flat-blade screwdriver through the end... then slowly work the screwdriver in while slowly rotating the screwdriver back and forth to separate the PIC away from the socket. do it slowly and try to reach the back before lifting the front away too soon.
Iwas gonna also suggest this method. However, although you can't always do it, I tend to try to twist just a little then do the same on the other end. Lather, rinse, repeat.
You want to be very careful so as not to bend any pins. Sometimes you can get lucky and can bend the pins back ONCE. ***If the bend is extreme, trying to bend it back to straight will result in the pin breaking off. ***
Like I said though sometimes close components wont allow room enough to do this on one end or sometimes both. If one end is blocked then you have no choice other then to do it just like Steve suggests unless you invest in a chip puller. However, sometimes close components dont allow a chip puller either.