Wrist strap keychains. This doesn't really need a tutorial but it's to remind me. Variations on the strap are a strap with clips at both ends (one for bag, one for pouch) and straps with clip at one end and d-ring at the other (for daisy-chaining or attaching multiples to a single); straps with a rectangular ring for tools are also good. And finally, straps with just loops for double or single carabiners!
Professional Zip Around Wallet by Cherie Killilea - Craftsy
Pattern to purchase. This wallet sewing pattern is a winner! Compact but still room enough for my phone, cards, cash, ID etc. Not for beginners but well worth the effort to sew this wristlet wallet pattern.