Penny - Penny is a personal finance app that takes the pain out of keeping track of your finances.
Socket.io - Realtime application framework (Node.JS server)
Zeta - Personal finance for couples
Ably - Serious realtime infrastructure
Spendee - See where your money goes
Pusher - Pusher is a hosted API for quickly, easily and securely adding scalable realtime functionality via WebSockets to web and mobile apps.