This is just a heads up for anybody that doesn't know because I don't think I've actually seen it mentioned on here.
Microsoft now do an Xbox Live Family Pack in the UK... the price states £70 but may well not be..
Me, my boyfriend and my two brothers share a family pack. Due to my boyfriend having another month left on his, and one of my brothers on his... we got it for £63, and each account for 13 months.
It doesn't necessarily have to be family.. they don't need to be on the same console at all times, you can just recover them to one console whilst you do it, then recover back. It's cheaper than buying 2 single years (obviously if it's for multiple people).
FAQ - http://www.xbox.com/en-US/Live/JoinLive/FamilyPackFAQ
If anybody decides to do this, there is a 'primary account holder'.. that person is the only person who can buy MS points off the dashboard.. they can also set restrictions on what you can do etc etc... so if you are going to do it make sure its with people you trust.