So, I'm a long way from an electrician. I can replace light switches, timers and outlets without major issue, but trying to figure out where wires go from box to box isn't really my thing.
Anyway, our electrical outlet in the bathroom has been tied to the bathroom light switch for as long as we've been in the house. Annoying as hell. The wife can't use a plug-in air freshener in the bathroom, and electric toothbrushes don't charge unless the light is on, etc. I've poked around in the electrical boxes (light switch is outside the bathroom, so separate boxes) a few times over the last few years to see if I could figure it out and change it, but no luck.
Well, yesterday, seeing as our new light fixture is dimmable, the wife asked me to put a dimmer switch on the bathroom light. I wasn't enthusiastic about having an outlet tied to a dimmer switch, so I had another look. Turns out the electrician who wired the house left a single blank wire run between the two boxes, not hooked up to anything. I checked for continuity, and confirmed it was the same wire. Jackpot. I rewired the circuits so that the outlet is now run off the hot side, and Bob's your uncle. Plug is now on all the time, and the light is dimmable. Kudos to the original electrician for leaving the wire.