Hero Holds are the number one thumbtack alternative, offering you a better way to hang your stuff with damage-free magnets.
How it works
Apply Hero Holds to each of your poster's corners.
Hero Holds work by sandwiching your poster between a magnet and metal plate, so no damage to your poster!
remove wall-side liners on your hero holds.
Attached to the back plate is 3M magic strip tape. This doesn't damage your wall either!
hang your poster corner by corner.
And viola! Your poster is hung beautifully, affordably, and with no damage to your poster or wall.