Since we already are required by law to carry our driving licence while driving most people just keep it in their wallet. This allows the police to stop and search you at any time and find out who you are. Stop and search in the UK does not require a warrant.
We're not required to have it with us while driving. If you don't have it on you the Police can demand that you take it into a Police station within 7 days though.
3 years is not that old for a PowerMac purchased in late 2006, and which now refuses to run Safari 4 and other recent software, since they require 10.6 or higher.
That's not actually true, Apple provide a download of Safari 4 for Snow Leopard (10.6), Leopard (10.5) and Tiger (10.4). That G5 purchased in 2006 would have shipped with 10.4, so you don't even need to have purchased any additional software in order to use the very latest version of Safari. You can download a 10.4 compatible version of Safari from here.
I really don't know where you're getting this 10.6 requirement from, because there really isn't one.
Chemist who falls in acid will be tripping for weeks.