I've got a Kenwood Frothie Maker - it's fab Makes the shakes hot and frothy - can also use it to make 'normal' hot chocolate, latte coffee, frothy cold milkshakes. It has to settings - 1 is a heat and mix the other is a frothy and mix. I don't make my soups with it but know others do (I prefer mine with the lumps in...!)
Couldn't live without my Frothie Maker - think they are around 25 - 30 quid depending on where you get it from.
Just found this one in Argos but it's the 'deluxe model so more cash!!'
Bought Frothie maker today, it is fantastic, makes my shakes/tetras much nicer than putting them in the mico, Kids have been having hot choc, milkshakes etc, hubby enjoyed his coffee made in it too, so it will be well used.