Just iPods mate, plugs straight into the top of the iPod - got mine today and have given it a quick test and it's awesome, can't believe something this small actually works!
You can get similar devices which plug into the headphone jack..
http://kryton.clickandbuild.com/cnb/shop/m...prodCategoryID=
There are others too, everythingipod.co.uk have other types of transmitters that work with any device...
This is the page you want - has all of them listed:
http://kryton.clickandbuild.com/cnb/shop/m...rodCategoryID=5