I must admit, i know squat about dongles and i couldn't find any good solid info on which one to buy and or, how to set it up.
So what i have done, for data on my laptop, using the correct data goodybag, i have bought a Samsung Galaxy Y (young or youth) for £50 at Argos, this is a factory UNCONNECTED handset (which is essential here)
After activating the sim online and adding the data goodybag I then popped in a new giffgaff sim, waited to receive the mobile internet settings to automatically install.
Now the Galaxy phones have a very easy to use tethering wifi hotspot function which has a reasonable range between phone and devise.
Job done ! i now have a good mobile internet service for a few quid a month.
BE WARNED !!! DO NOT USE AN UNLIMITED DATA GOODYBAG TO TETHER AS THIS IS IN VIOLATION OF GIFFGAFF TERMS & CONDITIONS AND WILL GET YOU DISCONNECTED FAST !!!