Pyramid Cafe, Luxor - Located on the casino level, reasonably priced
The Chicken Nachos are excellent! (and feed at least 2 people)

Mamma Ilardo's, MGM Grand food court - A decent focaccia-like pizza slice for under $4.

Sidewalk Cafe, Ballys - Excellent banana split for $9; can feed 2 people depending on the bowl they use :) Rachel and Alex ate here on their first vacation together.

Top of the World, Stratosphere - Go for lunch (decent prices and a ride up is included)

The Buffet, Golden Nugget, Downtown Vegas - The weekend dinner buffet includes crab legs and prime rib for about $20--a good deal in Vegas.

The Buffet, Bellagio - Best buffet, but you pay for it.

The Auto Collections, Imperial Palace - Free admission for AAA members

Hoover Dam, Boulder City (30 minute drive from the Strip) - Good place to see if you've never been.

Atomic Testing Museum (5 minute drive from the Strip) - A good museum with student discount

Liberace Museum (8 minute drive from the Strip) - Cool museum, but a little pricey.