Motorola is no stranger to mobile devices with two Sim-card slots, however with its Motokey 3-Chip handset, the bar has been raised to include a third. Aside from its defining trait, the Motokey 3-Chip is a fairly bog-standard Qwerty blower, with a basic UI, 2Mp camera and a Micro SD card slot with a capacity limit of 32GB. …
or different plans from the same vendor
2 SIMs are easy (work and personal) but you might want another one for 3g especially if you are serving wifi to your laptop form your phone.
Often the low-end voice plans have rubbish data limits - pop in an ipad data plan and off you go.
Expat Freelancers Mobile
This is great when you are a Euro-hopping contractor! One SIM for your home country, one for the place you are in and now maybe one for the last country you still have contacts in. I currently use a Nokia C2 dual-SIM mobile with a UK and an Irish SIM.