Go on your own personal scavenger hunt to create a souvenir to take home with you from Las Vegas. Collect a small item from each casino on the Las Vegas Strip. For poker players, this could be a $1 poker chip from each of the casinos. Go to the cashier at each casino and tell him you would just like to purchase a $1 chip. You can then frame these after collecting them, displaying your collection. Other options would be to collect a magnet or deck of cards from each casino.
There is a large variety of free entertainment along the Las Vegas Strip, especially during the evening. The Volcano at the Mirage erupts on the hour after dark, displaying a simulated volcano eruption. The fountains at the Bellagio perform a water show choreographed to music on a schedule that varies throughout the year. The schedule is posted in front of the fountains. When it's not windy out, the Treasure Island Casino hosts a live Pirate and Siren show outside the hotel on a stage created to look like a pirate ship. Harrah's outdoor Carnival Court features live bands in the evenings. Take a walk up and down the strip and take in all the shows.
Sometimes you just need a little time to relax. If your hotel has a pool, go outside and enjoy it. Some pools such as The MGM and Monte Carlo have lazy rivers, which are paths of water that circle the pool area that you can float along in on a raft. Other hotels such as Mandalay Bay have a wave pool where you can enjoy the simulated power of an ocean's waves. You might even see unusual sights, like the penguins at the pool area of The Flamingo in Las Vegas.
Take in the ambiance of "Old Las Vegas" by heading downtown and walking along Fremont Street. Fremont Street is a safe walking area patrolled by police that connects some of the older hotels of Las Vegas, such as Binion's, The Golden Nugget, Lady Luck and Four Queens Hotels. In the evenings at the top of each hour, a light show is displayed on the canopy that covers the entire length of the Fremont Street experience.