Twilio has a gaping gap in their service: there should be some very simple/easy out of the box solutions like "voice mail system" that you can then hook into with your own custom stuff. Not simple as in hack together a bit of PHP, simple as in click a few things on a web page.

As a small business, I really need a simple voicemail system, but don't need their programmable stuff. Yet. But it's cool enough that I suppose I'd go for them over others just to have it available if I want it in the future, if I got the simple voicemail system for a reasonable price.

I also tried Grasshopper, but their site barfed on my (very standard, plain) credit card.