Even though everyone thinks Vegas is sin city, what happens in Vegas stays in Vegas, etc, all the comments above ring true.
There are tons of things to do and ways to have fun, but hobbying shouldn't be one of them.
Personally, I can easily kill a couple of hours in the evenings just walking up and down the strip. The people watching is great.
The clubs in the casinos are abundant.
Shows of every kind. Restaurants, too.
Casinos for sure if you have some mad money to gamble.
If you like the outdoors, go to Red Rock Canyon. Nothing at all like the Grand Canyon, but only 15-20 minutes from the strip. Good hiking and pretty neat landscape.
If you have a shopper in your party, thee are two outlet malls nearby the strip. With our dollar the way it is, great deals to be had.
Golf. Use last minute golfer or one of those services to save a bundle.
Try
www.lasvegas.com It lists almost everything in and around Vegas that may capture your attention.
Have fun.