Jumping Out of a Rut? And a Rut-Busting (I Hope) Workout

I seem to be stuck in a pretty deep rut at the moment. Training, parenting, pet projects, work, you name it. But for our purposes we'll stick to training. I think my big three obstacles are:

1. Winter sucks. My basement, pretty dismal under the best of circumstances, truly starts looking like a prison by February.
2. Big (but largely good) changes in my schedule from last winter have left me without a regular workout time, and the times left to me are often abbreviated or during times where my body really doesn't want to do it. So I might have a choice of doing a 15-minute blitz midday (we don't need no stinkin' warmup) or a longer workout late at night when I really should be sleeping. The lack of routine is proving to be very difficult to deal with.
3. Motivation. I'm sure the schedule feeds into this, but ouch, even when I'm feeling gung-ho it takes a strong amount of will power to force myself to hit the intensities I'm aiming for, and when my heads not in it, it puts a big crimp in the quality of my workout.

Anyway, enough whining. Open question: How do you folks deal with your training ruts?

Here's a workout I tried tonight, trying to address my detrained state, and trying to build a warmup right into the workout to get my thick, syrupy, late-night blood flowing:

• Minute 1: 1 burpee.
• Minute 2: 2 burpees.
• Minute 3: 3 burpees.
• etc.
• Minute 10: 10 burpees.
• Minute 11: 10 burpees.
• Minute 12: 10 burpees.
• Minute 13: 10 burpees.
• Minute 14: 10 burpees.
• Minute 15: 10 burpees.

I bumped minutes 11-15 up to 75 seconds (told you I was detrained), and did lots of "just 3 more rounds and you can quit without hating yourself, you #$%@&$" self-flagellation to get through it. I hope this marks the beginning of a turnaround. After a couple months of just going through the motions, I'm due.