Hodlboard is a simple forum with "Inns" (a bit like subreddits) and "Solo" (for microblogging). It is a fork of freedit

Hodlboard exists to demo one extra feature:
    access to the forum requires ownership of a single utxo greater than 500K sats.

You don't need to spend the utxo, or hold it (despite the name!), it just needs to exist at that time. Moreover, which utxo is yours is kept hidden, using the power of zero knowledge proofs.
To generate the proof, you'll first need a keyset file, a large file of all the taproot pubkeys in the current utxo set holding more than 500K sats.

For how to get the keyset file, see here.

Once you have that keyset file, go here for exact instructions on generating the proof. Once you have the proof you can copy paste it into the signup page and start using the forum!