Swin2Sea,
This may seem like more trouble than it's worth, but here's one thing that helps out with the dilemma of storing and displaying pins.
1. Follow Erudolf's #1 & 2 suggestion.
2. If you have pins you really want to display, hit many cheap sources for frames for your collection. Go to local thrift stores and get something that would house the 'they're going with me to the grave' pins. IKEA's discount corner also is a good place to look as well.
3. Get black foam-core board. It holds pretty well for weight ratios and can be reused plenty of times. There's a selection of colors, but black seems to really class-up the shiny buggers pretty well. Cut the board to the dimensions of the frame. Can be found at Target or any art/school/ craft store.
4. If you have glass, that's fine. you may want to turn to plexiglass, as it is a safe and relatively cheap way of protecting your pins while protecting any shattering if the frame should fall. Measure the inside dimension of the frame (that holds the glass pane) twice, score the plexiglass, and bend to cut straight lines; use a Dremel tool for all other shapes (all houses should have one!).
5. For dimensional pins, such as diorama-style pins or multi-level pins, get cheap faux shadow box frames from Michael's Craft Store; use the standard 40% off one item coupon for a multi-pack, if they have them. Those usually have a plastic pane to them, but you can swap them for a thicker grade of plastic material; you may want to put foam-core board as the back plate to the box frame as the original ones are thick cardboard, which does not hold up well to weight.
It all requires some effort, but this has proven to be most effective with wanting to avoid from having multiple bags of pins and/or the desire to display your metallic addiction.
Hope this helps and good luck!