Yes - this is the stiff tape stuff - we had huge and uneven gaps between the floorboards and worked really well. Use an old credit card to shove it between the boards. I think they send you a free sample (or a cheap one anyway) so you can try it out before buying a lot.
Has been a lot less drafty since we did it (or DH did it and I made unhelpful suggestions). Which reminds me we must finish last bit..