Regarding the Photobox offer (Large collage for £1) i have searching for the cheapest clip board frames, and stumbled on this offer from Wilkinsons:http://www.wilkinsonplus.com/invt/0078696
I got mine from instore and these are great, good quality for £5.50. Iv not seen any cheaper!!
Only downside is that the size is 29" x 20" so depending how your collage is you may have to trim a side..