1. Anticipatory Transactions (yeah, it spends your money BEFORE you even tell it to == BETTER THAN INSTANT)
This is for real here, greek banks have been doing this for a while now
This is already implemented in Nxt:
http://localhost:7874/nxt?requestType=getTransaction&transaction=4016189039045729226{"sender":"11541844302056663007","fee":100,"amount":1000000,"timestamp":
-929,"referencedTransaction":"0","confirmations":45068,"subtype":0,"block":"14084146571794201371","senderPublicKey":"c729284d595e6cbcac232742b440bf7fe2f910adad46edf7b1540c3741977440","type":0,"deadline":1440,"signature":"71f66e217fa1e1c52d8d2988a20f58e46a172bd3653b3a9b2dbf45eaa1c41c0603f675361265ee2
d85f325ef5573d455cdf1dda4512f4581a83c8994360b9f40","recipient":"78880408059"}
This payment was made even before genesis block had been created.