Google Voice offers a really compelling set of voicemail features, much better than what US cellphone carriers offer.

You can view, search, and listen to your voicemails from any phone or web browser, with textual transcripts generated using automatic speech recognition.

Assuming you’re lucky enough to be on in the Google Voice beta, and have a GSM phone, here’s how you can replace your regular voicemail service with Google voicemai. (The Call forwarding entry in Wikipedia has a helpful list of GSM call forwarding codes.)

1. First, call *#67# and write down the resulting number, which is your current voicemail call forwarding number. This will let you go back to your old service later if you want to.

2. Next call the following numbers, where [phone number] is your Google voice phone number. (I’m assuming that you have your Google Voice account set up to go directly to voice mail.)

*67*[phone number]# (forward if busy)
*61*[phone number]# (forward if not answered)
*62*[phone number]# (forward if out of reach)

3. That’s it, your carrier will automatically forward calls to Google Voice when you can’t be reached. To undo the forwarding, just redo these steps, replacing phone number with your original voicemail number.