I blogged previously about how I've been getting on in terms of setting up an exercise routine - Getting started on an exercise routine again. After slacking on the home exercise routine quite a bit, I joined a gym really close to work (mostly paid for by my work). And went...maybe 4 times in about a month. I think it's a combination of not getting it done in the morning, the need to take an extra shower during the day, having to change clothes at work, etc - it's just a hassle unless you're exceptionally motivated, which I'm not.
On the positive site, what I have started now is doing a stair-climbing workout right here in my apartment building. Basically, I go up and down the stairs 3 times - that's 8 flights times three, so 24 flights. It takes me less than 15 minutes. Then I do a few squats and other exercises at the top, and call it good. My goal is to do it every day, but I'm probably actually doing it once every other day. I can tell a big difference when I climb the stairs now, in that I get winded a lot less. I think I'll aim to do 4 sets in about the same amount of time, so speed it up a bit, and then I'll be good.