I was playing "Money" ... The next time I looked up at the clock almost 40 minutes had passed.
That groove you get into when playing the bass is a whole different thing than when playing the guitar. It is like you wake up in your own little world with this infectious pulsating beat playing in your head, and because you are playing with your naked fingers (Maybe it is the same with a pick too?), you can literally feel the groove beating inside of you.
With the guitar you feel like you are fitting everything into these allotted spaces of time, where as with the bass you are the time space. If that made any sense.
This bass guitar thingy really is an addictive instrument.