How to Enter the US with Your Digital Privacy Intact
wired.com
wired.com
If you absolutely need something to make calls and check email, buy a non-smart phones for calls and take a clean laptop (e.g. a refurbished second hand machine that was freshly installed), but you can make calls from hotels and call from friends' phones. If you visit a department in your own international corporation, they can often provide you a guest loan laptop with the corporate profile pre-installed (including VPN).