Meh...ear wax is sterile anyways (but no less disgusting) so a normal wipe from a tissue would do the same most likely.
My source is my desktop so I can't lug that on public transit. My portable solution is only 256 kbps files (for the sake of space) so it's not a fair comparison to try. I can still bring my HD 650s with the black dragon cable if people wanna try it. Will also bring my e17 with e09k dock if needed (seems we already have a few).
Well...we have had someone bring their entire desktop to the meet once... That being said you should bring along your portable source if you have any portable headphones or IEMs you wanna try out. I would suggest bringing part of your music collection on a usb key, most of us will have laptops and I know for me, wouldn't mind others trying out their music on my setup.