Grab Singapore is currently having a Grab Singapore Sales. One of the deals from 31 May to 6 June is one that might interest you. Grab is selling 10k of their reward points for 10 Singapore dollars.
10,000 Grab Rewards Points to Miles 1
So why does this excites me? You are using 10 dollars to purchase 1k of Krisflyer Miles to be exact. Assuming you sign up for a grab account today, you are essentially getting 960 miles for 10 dollars. Not a bad deal I would say. You are getting 1120 miles for 10 dollars if you are a grab platinum user like myself. Great chance for you to boost your Krisflyer account for cheap.
While stocks lasts, limited to 1 deal per user.