Hey Energyzer,
On the contrary, Cary is actually a pretty nice (albeit not the most "happening"...) place in-and-of itself. As I'm sure you're probably aware, Cary is actually a suburb of Raleigh, and is considered part of the Raleigh-Durham metropolitan area. So, while there may not be a lot to do in Cary itself, you're a stone's throw away from any of the goings on in the Triangle. Here are just a few suggestions...
In downtown Raleigh, check out the "museum quadrangle" with the NC History Museum, the NC Art Museum, the NC Natural Sciences Museumm and the Children's Museum all within a stone's throw from the capital building. The capital itself is also kinda neat, as are the 150+ year-old churches flanking it. The NC Fallen Firefighter's Memorial is worth a look - very moving, and very unique. There are any number of great restaurants downtown, but some favorites include Sitti (Lebanese/Middle Eastern), Raleigh Times Bar & Grill, the Oxford (Gastropub), and (of course...) The Pit - which has SURPRISINGLY GOOD and authentic Eastern Carolina 'cue despite the "fancy puttings on" of the restaurant itself.
There's tons of shopping options within a 20 minute drive of Cary - pretty much all of the major malls in the Triangle have undergone recent renovation and cater to a more "upscale" clientele. For entertainment in the evenings, check out Goodnight's Comedy Club, the NC Symphony, the Galaxy Cinema (art films/independant) or any of the plethora of local bars and coffeehouses that host live music.
Unfortunately, the Carolina Hurricanes will be out-of-town during your stay, but if you're a sports fan, you're 30-ish minutes from two minor league teams, the Zebulon Mudcats and the Durham Bulls. Cary is also less than 45 minutes drive from Duke University, NC State University, and the University of NC at Chapel Hill - so visits to, or events at, any of those institutions would be feasilble.
Finally, one of my favorite restaurants in the Triangle - An Cuisines (upscale Asian Fusion) - is in Cary. DEFINITELY worth a try if you have time.
Enjoy your trip. Safe travels! :mrgreen: