Fleep

Fleep is a messaging service that fills the gap between email and various IM/texting services. You can add anyone into a Fleep conversation with their email address, until they sign up they receive your messages as normal emails.

You can even access your stuff from a browser! All you need is an internet connection. Your files and messages, pinned notes and history are always kept in sync on all the devices. n Fleep all your conversations form around a topic, files get shared and stored in File Drawer, important notes and tasklists are kept on Pinboard.