Just came across this on the internet for inquiring techie minds.
Travel Wifi - Mobile Hotspot Rental, Unlimited Internet, 4G ...
http://travel-wifi.com/default.jsp
Mobile Hotspot Rental with unlimited Internet everywhere in France. Starting at 5 euros a days, sharable among 10 devices.
Anyone wish to comment on whether this is worth the cost? I will not be able to find a cafe as I am with a group and (almost) every waking moment is scheduled.