I now take just a sandwich bag as a glasses case. There's a pocket just inside the door of my tent, on the side, that I put the glasses into at night so they won't get stepped on. I also use clip-on sunglasses, for which I do have a soft case that clips into the outside section of the shoulder strap pocket I use for my camera. If I want to leave my glasses off (i.e. horizontal rain), they fit in that case. I also have one of those roll-up film "glasses" that the eye doctor gives you to wear home after dilating your pupils. The weight doesn't even register on my 0.1 oz. scale and these are for spares and for bright high-altitude sun on snow.

For reading glasses, I recently tried a pair of i4u lenses (courtesty of Glenn Van Peski's gear list on the Gossamer Gear website and Bernie of Practical Backpacking who was giving away free samples). I never thought I'd like pince-nez, but these feel great and work fine for reading maps or reading in the sleeping bag. 0.2 oz. includes a soft case.