Hmmmmmm...
1. Grand Canyon is 4 hours away by vehicle; depending on time, you may want to reconsider (or take a helicoptor out there if you wanna hang with us ballers);
2. Rehab and Wet Republik (at the MGM) were the "in" places last year (no clue this year). Rent a cabana (for a few G's) and take your place as a true baller (WARNING: you will be AMAZED at how much money you can spend at either of those pool-side mega parties; they are meat-markets extraordinaire);
3. Nightclubs - TAO, Jet, Body English, Pure, Rain and XS were happening places when I was there; you may need to see what the "in" places are this year;
4. If you're the type, take in a show (e.g. Cirque de Soleil, etc.);
5. Hide your credit cards - shopping wise, there's the shopping mall at Caesar's Palace and across the street from Bellagio at Planet Hollywood there's a huge shopping mall attached to it (both are $$$$);
6. There are outlet malls at the end of the strip (huge one) if again, you like shopping;
7. Rent an exotic car and pretend to be a baller (note: those bastards have speed limiters on them, and you'll have to rent a bimbo to go with you as you're not allowed to drive 'em without said bimbo);
8. Gun store. 'Nuff said;
9. Golfer? TONS of courses to choose from (with a private one at the Wynn for $500USD a round to others, to Badlands at $200USD a round and Royal Links at $250USD a round);
10. Gambling? Nah, not in Vegas...;
11. Stratosphere Hotel, if you're not afraid of heights...there's a few interesting "rides" that should help you sleep at night...;
Other than that, the main strip is HUGE - it literally took us 15min to walk from the Bellagio to PH (which is across the street). The new complex beside Bellagio (where the Aria Hotel and Casino is) dwarfs the city of Toronto, and I believe there may be shopping in there (several hotels as well). So you can spend quite some time walking around.
Oh, I also recommend the Bunny Ranch/Chicken Ranch/Sheri's Ranch - the girls are friendly (don't you all judge me, she may be that type of girl...mmmmmmmm...wait, what?).