Pixum has taken 15% off all photo products as part of their summer savings sale. You also get free postage and packaging if you spend over £15 using the voucher code BU53234EH4MVF5G. That has to be one of the longest voucher codes ever.
Pixum has a range of voucher codes on their site actually, they seem to have a bit of a thing for them. You can get £2 off any order with no minimum value if you use the voucher code SUMMER13-2UK, you can get £5 off if you spend over £40 if you use the code SUMMER13-5UK, and you can get £15 off if you spend from £80 using the code SUMMER13-15UK.
You also get up to 15% off all photo products as part of their summer sale and I believe that this is part of the voucher codes that they have outlined above. Not great savings unless you spend a whack of cash at once and get £15 off.