Yes, although I usually end up doing my workouts at night when I have a cold b/c I'm too tired to wake up early in the morning. But a good run will often clear out my sinuses better than any meds.

I work out unless I'm too sick to get out of bed.

Yep.

Yes, unless it comes with a fever.

Just a cold? Yes. The benefits of that 30mins in the gym outweigh the cost of the lost short time of sleep.

Or do you skip in favor of rest? I'm not talking about when really ill or having breathing problems--just feeling under the weather.