Well, what you are asking for all depends on what you want to do.
For me, i chose to use the Linksys WRT54G wireless router:
cgi.ebay.com.au/LINKSYS-WRT54G-W … dZViewItem
Well i was able to install OpenWRT onto it, which then meant i was able to install a skinny version of Asterisk onto it as well, to top it off, it uses less power then a computer, and you can also keep it as a wireless router and also a 4 port Ethernet router.
It doesn’t take much to configure it, but i tell you it is worth it all the way, and fr what you can pick these things up for these days is amazing, especially when you yourself know what can be done with it.
I was at one stage even thinking about customizing this so it can be used for businesses as well, it barley goes down, and you can set it up so voice mails are directed to another server, this way nothing is stored on it as it does not have enough room really to hold voice mails.
Thats my take, i am sure others will have some kewl things to share as well.