Small Wi-Fi Routers

I can imagine some instances where you want to quickly set up a WLAN consisting of a few Raspberry Pi.  Internet access would not necessarily be a requirement but using DHCP to hand out a few addresses would be.  Has anyone had good luck with a small wireless router ?  Ideally the administrator screen would play well with mobile devices ex: an iphone or ipad.  Then after I see the RPis are working, I could log out and leave it along until it was time to disassemble the demonstration.    -- Scott KD5NJR