Sorry late response... One is WiFi Analyzer. Shows Channel, strength, encryption, ssid. Has a nice little great with signal strength along with min/max/avg. Not sure if you can get it from appstore now as someone else pointed out can get OpenVPN officially there now :)

Also... I'm curious as to why Apple hasn't added a SBSettings / NCSettings type feature as most other smartphones have toggle buttons in the "notification area" which make life a lot easier.