What's a really nice birthday present for a boy turning 5?

A really nice gift. He has every car and truck you can think of. He has a bike, a power wheels, a scooter, a work bench (although he's already outgrowing it) a basketball goal, a ball pit/jump-o-lene, a train table,sandbox, swing set, see-saw....
So any ideas?

his dad says no to a trampolene

a large remote control car, Lego's, transformers, a larger more age appropriate work bench, a digger or a twirly bouncer. both outside toys that you put in the ground. the digger has a seat and you can dig in the sand. the bouncer is similar to a see saw for one person and you jump and twirl.
you could also go to toys r us and search by age and gender and get some ideas. They have some cute sets that are like castles (but for boys)
best of luck

how about hot wheels?

Legos has some awesome kits and Nintendo DS with the Yoshi's Island is big, Game Cube has a bunch of kid friendly games, slip and slide is awesome. Transformers are cool.

how bout cash and then take him shopping....everyone loves cash

take him shopping at the biggest toy store you can find tell him you are looking for another kid and see what he plays with

get him some train track and trains

A webkinz. You could get him the loin (its very cute) and maybe a pack of trading cards or a webkinz charm. they are very fun and teach great skills.

For more info visit webkinz.com

Another idea is to get him a membership to Club penguin.

A Webkinz

i say a bicyical