One of the best deals at FoQ (in my opinion) was a stall that just sold ribbons (all brand name, top quality). I hadn't come across them before. Have a look yourself:
http://www.FantasticRibbons.co.uk
You have to buy whole reels, but at any 4 rolls for £6 (and it gets better: any 20 rolls for £20), this is a very attractive offer. I go through a lot of 3mm ribbons, so I stocked up. But you could always get together with friends in order to get the best deal.
The only other big purchase I made: Two length of hand-dyed cotton and one length of hand-dyed silk (mega-yummy) from Frieda Anderson and Laura Wasilowski. By buying these fabrics at FoQ I saved myself the VAT and admin. charge that we normally get clobbered with if ordering from the US (somehow whatever I want from the US ends up being over the very mean limit of about £16).
Lorchen