For now, most iPhone enthusiasts are stuck using a tethered jailbreak, which requires users to connect their handset or slate to a computer and run either Redsn0w or Ultrasn0w after each reboot.
However, there is a toll that can help. SemiTether, a tweak currently in beta, is available from the Cydia Store, a third party market built specifically for jailbroken iOS devices.
SemiTether allows users to reboot their jailbroken device without being completely shut out from their device. While users cannot access most apps after a reboot, including Safari and Mail, they should be able to make calls and send text messages.
While hackers search for a way to perform an untethered jailbreak on iOS 5, SemiTether is probably the next best thing.
SemiTether is incompatible with the iPhone 4S and iPad 2, as there is no way to currently jailbreak either device while running iOS 5.