Replacing landline with VoIP+Cellular

Replacing landline with VoIP+Cellular

I currently have a landline provided by SBC/ATT costing me $25-$35/mo that I have been wanting to replace for quite some time.  I have 3Mb/s cable modem service, and was waiting for Charter Communications to come forth with its 'imminent' telephone service.  They finally called a few weeks ago and offered me unlimited telephone service for $39/mo - no savings at all.

The real issue with this (and Vonage, and my new mobile provider's 'unlimited' plan) is that I don't really need unlimited service.  Our combined local, long distance, and mobile (x2) usage is <300 minutes per month.

I want to completely replace my existing landline with some combination of my existing mobile and broadband services, and attempt to save the $400-$600/yr I have been paying to SBC/ATT.

Although I have done some research, I would very much appreciate some insight from those that have done this before.  Here are the facts:

- I want to drop my residential landline.  Residential, not business (or even small business).

- I currently have 3Mb/s cable modem service, via Charter Communications.

- VoIP local number (Skype-in, Vonage, Gizmo, SIP-in, etc) does not seem to be an option here on the California Central Coast (San Luis Obispo).  I have not found any VoIP service that can provide me a local telephone number.  None have a local point-of-presence. The closest would be up in Silicon Valley or down in Ventura county - either >200 miles away.  "Having a prestige area code" arguments aside, most of the calls we receive are placed locally.  Forcing our friends to call us using local-long-distance (the highest possible rates) would be very unfriendly.

- Number portability seems to not be an option here on the California Central Coast (San Luis Obispo). (Same reason as above, I suppose.)

- I am aware of 911 calling issues.  In our area, only Vonage supports it.  We still have 911 service on our mobile phones.  If we reuse our cordless phones, I can program an autodial number for police, fire, etc (although these are non-emergency numbers).  I can put the router and cable modem on a UPS in case of power outage.

- Our mobile account (via Cellular One) has 600 mins/month for 2 phones, with nation-wide long distance and California-wide local calling area (no roaming in CA).  This a very old plan that is much better than the currently offered plans.  If make any changes, I will be "promoted" to a newer plan, where the second phone goes from $5/mo to $19/mo and my local calling area shrinks to SLO county.  The latter would be a killer, since I frequently travel between the SF Bay Area and LA.

- I have a small network of machines, using a Linksys BEFSR41 switch/router connected to the Motorola Surfboard SB4200 cable modem.  I also have an Apple Airport wireless network (behind the router). I have read instances where placing VoIP hardware on the DMZ and/or between router and cable-modem may improve quality of service.  I am open to replacing the Linksys router, as it is a complete piece of crap.

- I was considering getting an analog-to-VoIP box so I could reuse my existing 3 satellite cordless phone system.  This benefits my wife ( the techno-luddite whose doesn't even use auto-dial ) as well as the convenience of cordless phones.

-  Although I run a small home business out of my home, I don't think I need an asterisk-like PBX.  Most of my business communication uses email, instant messaging, and video conferencing using iChatAV.

- My wife is English, with family and a small business in England (UK).  Most communications are via email, but she does make 10-30 minutes of calls to the UK each month.  Although we have 'free' US long-distance on our mobile phones, international calls from our mobiles are prohibitively expensive, so this should be covered by VoIP (or calling cards?).

- My primary desktop and servers are Mac OS X, so Windows-only software is not an option.  I am considering Skype or Gizmo software-only service as they are Mac-friendly (especially Gizmo).

- My goal is to reduce telecom costs, so I don't want to fork out $500-$1000 for new hardware.  I can probably justify $50-$150 initial outlay.  $25-$40/mo services are out of the question, since they cost as much or more than I am paying now for my landline service.

- I am reasonably technically competent (note my numerous EE expert certifications), so I am comfortable setting up hardware/software/services.  My wife, however, would not tolerate an overly complicated super-geek solution for daily use.

That is basically a dump of what I have been mulling around in my brain.  I look forward to hearing your advice and experiences.