BYOD Isn't new
I've worked as a consultant for many years and have always used my own mobile phone for work as well as personal use, there has been no additional cost for me in the UK as my voice plan has always been able to cover both uses. Historically I've tended to use a client provided laptop with a secure VPN connection and whole disk encryption to give me access to the client network and email on the move. I now find that I'm using Citrix more to get access to network resources at home via my own PC and broadband and a company provided smartphone to get email on the move. this means I'm carrying two phones for the first time in my career but not carrying my own laptop around as much as my own smartphone will accomplish what I need for personal use during the day.