Collect your favorite number forever! Mint a new token by calling the "add" contract function with payableAmount = 0.002 and both tokenId1 and tokenId2 set to existing token ids. This creates a new token in your wallet with id = tokenId1 + tokenId2, assuming this sum doesn't already exist as a token. The owners of tokenId1 and tokenId2 each receive 0.001 ETH of the 0.002 ETH fee. If you use your own tokens for minting, then the minting fees will return to you. As with any blockchain transaction, there is an additional gas fee to take into consideration.