Christmas Presents and Kindles

Thank goodness for work giving early Christmas presents!  In the past 3 days I got a little portable TV and a Kindle.  More gadgets to add to my growing collection.  But I'm worried these might not be the best gifts for me.  I can't remember the last book I bought - I tend to borrow those.  And I rarely watch tv at home, so why would I need to take a tv with me somewhere?  I don't know, perhaps I'll find a cool use for it.  I think I need to read a little more about the Kindles to see if I want to keep it.  I don't even know how much electronic books cost.  And can you share them?  Like, if you had a book on your Kindle, could you transfer it to mine - like I was borrowing it?