Getting rid of the boredom is the key. If you don't like it, you won't do it. Are there any sports that you like that you could do a couple days a week? How about taking a class...a few folks have mentioned samba, or martial arts?
I feel your pain with the treadmill. I play tennis 2-3 times a week but the weather has been so bad that I have to replace that time on the 'mill. Having good music really gets me into it, so I treat myself to music downloads and create playlists to get me through it. Once the music starts going I get more and more into it and the time goes by okay.
And now that you don't have to be perfect, you can be good.