We have a couple of Royal Umbria 50oz sleeping bags. They are great but the storage bags that they came in don't compress them down very much. They are made from clear plastic stitched together so they they are likely to tear along the perforation of the stitching. So I have been looking for something to replace the storage bags for a while. We have a couple of other sleeping bags that came with stuff sacs to store them in. You can buy stuff sacs separately but the ones I had seen were quite expensive £6+ for what is basically a polyester cylinder with a drawstring.
There was a forum post on the camping forum by someone who had fitted the same sleeping bags into stuff sacs made by Gelert. (These pictures are from that post)



So our sleeping bags fit into these Gelert stuff sacs. The post had a link but where they were £3.50 each and I was tempted but never got around to getting any. Then the other day I found them for £1.50. I couldn't resist any longer, there was a £5 P&P charge so I got a bundle of them, some large (the one pictured) and some extra large (£2). I reasoned that they will be useful for all sort of other things, especially extra duvets and pillows.

The large one is 19" x 10"/48 x 25cm and the extra large is 24" x 12"/60 x 30cm. They arrived this morning and seem well made and pretty sturdy. I think they will get a lot of use. They said they were assorted colours but when they arrived they were all blue.
Compression sac
I should have mentioned that they sell compression sacs too for £3 http://www.family-camping-supplies.co.uk/item.php?cat=8&i=140