We got some instead of keepong some money in a savings account for some work I need to do at the office when we get approval for it. The NS and I website says that the prize fund is 1.5% of the total invested, which they take out bonds on so they are earning money and giving out the equivalent of 1.5% interest a year averaged out over a lifetime, which is as good as most ISAs these days, is instantly accessible, it's 100% dependable and you never know you might win £1m!! What's not to like!