You can always tell a real gigging musician by the proximity of the PA gear to the front door (if it's not occupying the garage of course)

I think Mary and I qualify for most of the other things mentioned here.
Apart from instruments that we play, I've noticed that most musicians accumulate a number of instruments that they don't play but are hoping to start learning "some time". The number of these reaches a limit: you're dissuaded from buying any more when you remember how many things you have hanging on the wall that you haven't started on yet (in our case a hammered dulcimer and a Bulgarian gaida, kaval and tambura, not to mention various whistles)

The rest of it looks horribly familiar:
Home studio with mics up on stands, instruments in most rooms of the house, music, bottles, empty glasses and coffee cups...

Anahata