It solves a problem, if the only computers you can use: - are slow and virus-ridden. - don't belong to you, and you have shared or sporadic access (not a good

It solves a problem, if the only computers you can use: - are slow and virus-ridden. - don't belong to you, and you have shared or sporadic access (not a good place to leave your files). - don't have the software you want, and you can't install programs (or do much else) 'in case you break it'. There's not ONE overriding problem to be solved, this is just one way for people using shared computers to get their own secure and consistent environment. Plenty of people (in Western countries) carry around USB sticks with their files and some portable apps; this is just a logical step further.