Sorry about writing about the 13 bitcoins, I was writing it for another person and by mistake it ended up here
You see, there is an option to edit the title of the post on this forum, you may want to use that.
Anyways, here are my favourite parts:
1) Low tx fees.
2) Can be used from anywhere (unlike services like paypal which isn't supported in particular countries)
3) Pseudo-anonymous. But gives you amazing privacy if you use it correctly.
4) Security(again, only if you use it correctly.)