I like all the travel workout recommendations. Do you ever stay in a hotel with a gym? If so, iTrains and Cardio Coach downloads comes in handy...they have ones for the bike, treadmill (walking or jogging), elliptical or stairclimber). iSculpt traditional 12 with Mimi (another iTrain workout) does not use any equipment. Other workouts with no or minimal equipment
Cathe Travelfit
Cathe Slide and Glide (uses discs and band)
any yoga if you can manage a mat
Any Cathe kickbox workouts, esp my favorite, KPC
P90x if you use the band options
Hi lo cardio if you have the room.
There are some of the new Tracie Long in the focus series that don't have equipment, I THINK, but not sure which ones as I don't do the focus ones that often.
If you're into barre stuff, many of the ballet bodies don't use equipment and you could use a chair for your barre.
Tony Horton has a one on one DVD that is a travel DVD, but I can't fully recommend as I haven't done it.
Jillian Michaels Burn Fat Boost Metabolism uses no equipment.
I have both a gym membership and my home gym. I work out in the morning, so sometimes getting to the gym is a complete pain in the bootay.
I go through phases. Sometimes I am a gym rat for awhile. For a long time now I prefer working out at home. However, my plantar fasciitis is acting up so I see myself going back to the gym to use the stairclimber and elliptical as they won't exacerbate the fasciitis. It helps that my husband teaches a class at the gym so our membership is only 20.00/month...I don't feel as guilty when I don't' go.