Bit random but here goes!
Had to buy some timber and found this the cheapest anywhere. Cheaper than my local building merchant (MKM).
Single CLS Timber - 38x63x2400mm £1.95 each. Available in store at Homebase.
CLS equivalent of old school 2" x 3".
£2.98 in B & Q. Even the multibuy (20 off) is £2.