Ok, I know I'm breaking my rule about explaining hacks but I think this is kind of important.
My cell company changed my voice mail so that it didn't require a password to retrieve my messages.
I occurred to me that this would be an incredibly easy hack to break into my own vm.
Depending on your carrier and type of trunks this works - I know, I tried it.
Simply go to the associated number directory form and change the CPN for your desk phone to match the cell you want to hack.
Now just call it. When it rolls to VM you're in.
So, be sure your cell phone voice mail requires you to enter a password.
Ralph