A blog that follows you around, a single number for all your phones, and an automated reminder service top the betas on display at O'Reilly Media's Emerging Telephony conference this week in the San Francisco Bay Area.

Of course, it's a long way from free beta to booming business (or multi-million-dollar buyout), but here are a clutch that have a good chance to hit it big.

Grand Central

Are you ready to be your own telecom mogul? Grand Central lets you use a single phone number to make and receive phone calls from all of your phones: Answer a call to your office number on your home phone, for example, or make a cell-phone call on your office phone.

Your number persists as you change your residence, get a new job, or sign up for a new cell account. Other features include integrated voice mail (including the ability to listen into voice messages as they're left, and interrupt the message to take the call), and greetings tailored to a specific person or group. The beta is free, but the service is expected to cost about US$50 a month when it's officially released later this year.

Jaiku

Jaiku goes personal blogging one better by letting people know where you are, what you're doing, how you're feeling, and just about anything else you'd like to share about yourself. Load the free beta service's mobile client on your phone to text presence updates to your shared calendar.

ReQall

Still in private beta is ReQall, a service that lets you place a phone call to yourself--or send yourself an e-mail--to remind you of impending events. You can set the reminders by calling a toll-free number from any telephone, and the service's downloadable applet for Windows XP lets you send and receive reminders via your PC.

The service converts your voice message into e-mail text using a combination of speech recognition and human transcription. Worried about confidentiality? The company claims the transcribers can't match messages to the people who create them, but I think I would avoid sharing any trade secrets via the service.

After Hours Doctor's Office

The conference's mashup winner was After Hours Doctor's Office, Thomas Howe's voice-mail/callback system for phone calls received by doctors from patients when the office is closed.

The system uses the human medical experts on duty at Amazon's Mechanical Turk artificial intelligence beta service to determine whether the call is a true emergency, or just a "take two aspirin and call me in the morning" situation.