Ok just returned from my second ever bivi adventure. I've not got a mat and spent the night in my sleeping bag inside my ex-mod bivi bag, now I wasn't cold but think I would slept much better with a mat.
I've been looking at the Alpkit mats and they look great but what I think is a bit on the large size, my mate had a balloon bed which was great but woke me 3 times in the night with a massive bang!!!!
So what have you got? I dont want to go and spend loads but I guess if I HAVE to I could ))))

The 'best' mat I've used so far has been an Exped Synmat UL. Pretty light, dead comfy, very warm and a good pack size.

Others seem to favour NeoAirs ... good offer on small ones here - http://www.theoutdoorshop.com/showPart.asp?part=PN57175

That looks like a good price and great reviews )

You can go lighter but bulkier with a decent foam mat - (see multimat for the highish end of that spectrum) -nowhere near as comfy as an air-mat, but you can cut it to shape, slice it into segments if desired and it's cheap as chips too. Also if you stab a hole in it, it'll still work.

Just remembered this; http://hikinginfinland.com/2009/12/gear ... esses.html

I bought an inflatable mat for about £20 and it was really poor. I then spent about £100 on a NeoAir XL from thermarest. It is very comfy for side sleeping, light and packs down to about 1ltr.

Klymit static V. I'm 6'2" and needed a longer/wider mat. Imported from the USA, very happy with it. Packs small and light.