The tesco clubcard sale has its final offer for this session launched today.
The offer is for national railcards at a bargain rate of £5
The normal clubcard rate for a railcard is £15 of clubcard vouchers to get a railcard (normal railcard price with cash is £30)
Previous clubcard sale items have also been great value with me picking up some itunes vouchers and pizza express vouchers, but all the others have now sold out.
Looks like variable amounts of each card available at the start but going reasonably quickly. I'll try and give some updates on availability in the comments below.
Update at 2pm
The friends and family ones are sold out, but still some 16-25 (150), disabled (350) and senior ones left (250).