Check out Nootka Plug your bass into your computer, and Nootka will display notes that you need to play on your bass. Pitch detection knows whether or not you're playing the correct note. There are many others useful methods to help learning and practicing reading music. Choose a key, set up custom notes and positions to learn, etc. It's a work in progress, and a little rough around the edges, but once you figure it out, you'll realize what a phenomenal training aid it is.