If power consumption isn't an issue, is it worth my time to power up an old laptop and have it CPU mining? It's only like 5 years old so it's not a great CPU.
The laptop is pretty much dead to me anyway so I don't mind if it's quickly killed by the process.
Probably not worth your time/effort if you're looking at it in a fiscal sense. If you're just looking to experiment/play around it might be a place to start. You won't make money off of it, but you might learn something about Bitcoin mining and Bitcoin in general.