Hot Air Ballooning 

If you work for, at, or even near NASA, you probaby harbor a secret (or not so secret) ambition to climb into the sky on a stream of fire.  In this case, the flame is being used to heat the air inside a big honkin' fabric bag.  It won't get you to Mars, but you'll pull fewer gees during your launch.

Keep in mind that balloon rides are susceptible to bad weather.  Which is to say, if the weather is bad, your flight will be rescheduled, so if you're leaving two days after you're planning your flight, make sure the company has a refund policy in case of bad weather.

Balloons Above the Valley

Description:  If you've ever been to a cocktail party you know that mixing hot air with wine is not exactly a novel concept.  Adding a balloon to the mix is fairly creative, though.  This company flies in the Napa Valley region, and many of its flights involve wine tastings, wine lunches, and the like.  They also offer a number of "balloon and accommodation" packages, so you can spend the night at a bed-and-breakfast and then fly around the next day.  Note that they gather for flights at a different location than their business office; namely, the Napa General Store at 540 Main Street, Napa, CA.

Web Site:  http://www.balloonrides.com/

Location:  603 California Blvd, Napa, CA (office)

Drive Time from Ames (per Google maps):  1 hour and 35 minutes to 2 hours and 30 minutes (it's about the same to either the California Blvd or Main Street locations)

Public Transit: 

Hours:  Flights are by reservation only, but it appears that you can reserve them year round and on any day.

Wine Country Balloons

Description:  Another balloon company operating out of wine country.  This one specifies that the rides are typically an hour to an hour and a half, with a "the whole experience" taking 3 to 4 hours.  "The whole experience" apparently includes a champagne brunch, and possibly other activities.  This company also offers bed-and-breakfast packages with their flights.  Like most balloon companies, they launch from a different location than their business office; in this case, their launch gathering point is 397 Aviation Boulevard, Santa Rosa, CA.

Web Site:  http://www.balloontours.com/

Location:  Sebastopol, CA (office; no specific address given)

Drive Time from Ames (per Google maps):  1 hour and 51 minutes to 2 hours and 10 minutes (it's about the same to either Santa Rosa or Sebastopol)

Public Transit: 

Hours:  Flights are by reservation only, but it appears that you can reserve them year round and on any day.

Cost:  $225 per person