Timeline

• June 29, 2007 -- iPhone is released. World's most hyped consumer product.
• July 3, 2007 -- DVD Jon first cracks activation. People can use the apps on the phone without a subscription
• July 9, 2007 -- dev team releases jailbreak method. The first use of this is ringtones
• July 20, 2007 -- nightwatch ports a toolchain to the iPhone. The first apps are compiled. (but see "Revisions needed" note below)
• August 14, 2007 -- First phones are used with other carriers by means of a SIM hack
• August 21, 2007 -- Installer.app is released, first GUI apps are distributed
• August 23, 2007 -- geohot and team release hardware unlock method.
• September 10, 2007 -- IPSF releases first software unlock method for money.
• September 11, 2007 -- dev team releases iUnlock, first free software unlock
• November 2, 2007 -- jailbreakme is released, bringing jailbreaking to the mainstream iPhone user
• November 15, 2007 -- New bootloader comes out, new iPhones can't be unlocked.
• February 8, 2008 -- geohot releases software unlock for 4.6, Apple states 25% of phones were never activated with AT&T
• February 11, 2008 -- Zibri releases ZiPhone, the all in one unlock, activate, jailbreak solution.
• July 6, 2008 -- yiphone.org is registered in what turns out to be a failed attempt at conning the dev team to release software before it's ready.
• July 11, 2008 -- iPhone 3G is released
• July 19, 2008 -- dev team releases PwnageTool, jailbreaking 2.0 software on iPhone and iPhone 3G

Revisions needed: Nighwatch didn't "port a toolchain". Also needed are references to iAsign, iNdependence, virgintool, sam+daeken bruteforce.