-take breaks while recording, 3-4 min walks are great.
Oh yes, they're a lifesaver. My normal rule of thumb is that if I try two things in a row that just blatantly don't work then I'll go for a walk for a few minutes.
I'll also add - learn to differentiate between feeling creatively driven and just feeling bored. When I'm bored, I'll just do sampling stuff, or put together patches on my more labyrinthine gear for later use. Trying to record stuff with no real creative urge going on is just a frustrating and depressing affair.
Now as for stuff that's more relevant to the thread - Recording the acoustic noise of electric instruments is a very fun thing. Record an electric guitar through an amp sim and simultaneously mike up the strings. Either EQ the sound to pull up all those lovely transients or drop an enhancer on it (I like to use Character
on the Powercore) and lay it over the top of the amped sound. Or mic up a bass guitar and lay the plucking and string noise over the top of a synth bass sound - it gives it a whole world of attitude, and you can punch it in at key points to give the bass track a bit of needed emphasis.
Recording real sounds is fun, do it as often as possible. I spent half an hour today whacking a pie tin with a wooden spoon just to add that 'little something' to a drum mix.
Use a gate with a slow attack to soften the transients of drum sounds that have too prominent an attack. It doesn't stomp all over the rest of the sound like EQing would. I use this on kicks that have a clicky attack, like a lot of analogue drum machines.
Parallel distortion is cool when you want grind in a sound but find running it through a pedal destroys all the dynamics. Put a distortion pedal on an FX send and record it to a separate track, then EQ the original and the effected tracks so that they complement each other.
Ugh... I should be able to come up with more, but it's late and I'm tired.