I've managed to drop from about 290 to 260 (I'm 6'6") over the last 6 months or so, and am still gradually losing more, with exercise, but no change in diet. I used to never be able to discipline myself to exercise, and got bored and stopped after a few minutes, or tried it few times and then stopped getting around to it. However, I managed to start up and actually keep going by combining exercise with games. I basically use a stationary bike while playing video games (started out using a gameboy at the gym, and have since bought one to use at home rather than maintain a gym membership). The time goes pretty quickly, and I don't have the reluctance to get started that I used to have (actually, I tend to look forward to it if I'm in the middle of a game I'm enjoying), so I've been able to pretty consistently do an hour a day. I'm sure I could be losing weight faster if I altered my eating habits too, but I've been able to make consistent progress and keep eating the foods I enjoy, so I'm pretty happy about this system.