Gift for 5 and 3 year old boys?

Hello ladies sorry to crash.

Was wondering if your 5 or 3 year old boys are into something really awesome that I am not aware of. Am going to a birthday and want to get them something out of the ordinary because I love them so

If it helps any the older one is obsessed with Ben 10 and the younger one still has an obsession with Thomas.

Any ideas would be great and much appreciated