O2 UK - not known for being the most ambitious of carriers on data strategy - has followed Vodafone (NYSE: VOD), T-Mobile, 3 UK and even Orange by launching its own mobile broadband laptop dongle. The device is of the slimline USB stick design for 3Gb monthly allowance and, starting at £20 ($40) per month, is a full £5 pricier than Vodafone’s currently discounted £30 per month offering. But the kicker is that O2’s stick also packs in WiFi, and a deal with The Cloud WiFi operator allowing it to be used at over 7,500 UK hotspots on an unlimited basis. The device will switch users between GPRS, EDGE, 3G, HSDPA or WiFi, depending on the best available - that’s up to 1.8 Mbps right now on the cell net, up to 3.6 Mbps from June. This while other nets upgrade to 7.2 Mbps. 3 UK this month reported its data traffic had risen 700 percent thanks to the introduction of its mobile broadband USB dongle in October.