Jump forward to about 1 month ago and I was in, of all places, my local Home Depot store and walking past a Christmas gift display of cellphone related items. And that's where I spotted something called "Mobile Man", which is a rubber coated, flexible, person-shaped device to hold your cellphone and hang it off things via the hook at one end; a photo will show you what I mean better than my words, so here it is:
The entire thing has a flexible wire skeleton that allows it to be molded to shape/size to suit. The hook means I can hang my phone from my tripod and and be secure in knowing it's not going to fall. This little guy only cost around $5 which to me makes this a huge bargain and really hard to beat for anyone wanting a means to quickly attach their phone to a tripod.
Here's another photo with it actually holding my phone: