21OS

Educational notes on running your money like a treasury.

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RiverCash at 3.50% APY (as of Oct 3, 2026; can change), interest in bitcoin or dollars.River isn't a bank; cash deposits are FDIC insured through Lead Bank (pass-through, up to applicable limits). Bitcoin isn't FDIC insured. Not available in every state. Not financial advice. Simple MiningHosted bitcoin mining. New customers get a $100 hosting credit.Mining results depend on bitcoin's price, network difficulty and uptime, and aren't guaranteed. Equipment may be depreciable for some owners; ask a CPA about your situation. UnchainedCollaborative 2-of-3 multisig and inheritance planning. $50 off a vault.Unchained never asks you to send bitcoin to sign up. Educational, not financial advice.