This guide explains how to fully activate iOS 5 beta for non-developers without crippling your iPhone or iPod Touch. Notifications work, push works, multitasking works, sync works and iMessage works. If you've already installed iOS 5 skip to instruction 4 and if you've already installed and jailbroken skip to step 5. This tutorial is unlikely to work on iPads and since the redsn0w beta is mac only you must have a mac.
1. Download the iOS 5 beta firmware (torrent or http://imzdl.com/#)
2. On your device screen in iTunes 10.5(Download from above link) hold the shift key and click update
3. Select the beta firmware you downloaded and restore it
4. Once the update has finished use redsn0w(download) to jailbreak your device. Once its jailbroken open redsn0w again and select "just boot tethered" from the second screen
5. Once your device has finished jailbreakng and the lock screen has loaded triple tap the home button to turn on voice over
6. Tap the status bar then drag with 3 fingers from the top of the screen down to the bottom to open the notification center
7. Triple tap the home button again and click on the Yahoo logo to open the stock app then press the home button to get to the springboard
8. Open Cydia, go to the search tab, search for iFile and download it
9. In iFile navigate to the location and open it in the property list editor
10. Remove the release type key and save
11. (iPhone only) Go back to Cydia, add the source "http://repo.bingner.com/" search for "SAM" and install SAMSprefs
12. (iPhone only) Go into settings, then SAM, and setup the carrier
13. Reboot your device and boot tethered with redsn0w and setup your device.
Once you've done this you'll be able to use multitasking, iCloud, syncing and iMessage along with all the other features that required activation to work!