I occasionally -- by which I mean "once, since bringing it to work six months ago" -- go down the the lowest parking garage level under my building at work and play my guitar. There's a concrete pillar that has a power outlet -- so I can plug in my amp. Next to the pillar is a space between some bike racks which is protected by railings -- so I can set up and be safe from getting squished by cars.
I point my amplifier away from me, to maximize the amount of natural reverb compared to the direct sound -- and I noodle away during my lunch break.
So, I did this once, about a week after first bringing my gear in to work (the first week of November, 2014). (Holy carp -- it's April 2015! How'd that happen?) And for the last month I've been meaning to play "basement guitar" again.
Well, today's workday was making me feel a little futile -- so I went "eh", and went down during my lunch break.
I enjoyed it. And I amused the security staff. :)
In related news, I'm playing guitar more often than I have in a loooong while: about once a week, maybe a little more. I've been inspired by a co-worker who is playing nearly every night. I figure: I enjoy it; I should do it more often.
I'm being fairly non-instrumental (pun not intended) in my playing: I'm not recording, or trying to come up with song ideas. I'm just noodling around with different scales, expressing myself, and enjoying the experience. And in the process, presumably getting better at playing the guitar.
Finally, a comment about the guitar (pictured) -- which is the guitar I have under my desk at work. It's kind of quirky -- but, I like quirky. I picked it up for AU$59 (about US$43), because (as you can see in the photo, before I repaired it) two of the grommets on the tuning pegs were missing: I repaired this by fabricating wooden "sleeves" to take up the space. Also, the tip of the pickup selector switch is missing, and the volume and tone knobs are different styles of knob.
But, again -- I like quirky guitars. :)