You must have seen this a hundred times now but there is currently a promotion (again!) which gives you up to 50% more Mileage Plan Miles when you purchase between now and 05 October 2017. As I have mentioned many times before, you can use these easily for Business Class flights on Japan Airlines (JAL) for less than US$500.
I always mention Japan Airlines but the truth is, you can use these miles fairly easily across all airline partners (including Cathay Pacific, Hainan Airlines and Korean Air if you are in Asia). You should definitely check the Award Chart before you purchase any miles so you buy enough. If you do intend to redeem these miles for Japan Airlines, make sure you try to get a flight that features the newest SKY SUITE III product (check out this YouTube video that some guy made!).
Since Japan Airlines is part of the oneworld network, you will be eligible to use any one of the participating oneworld lounges when you redeem for a Business or First Class award ticket. If your account is targeted for the 50% bonus, you can essentially fly from Singapore to Tokyo and then to Kuala Lumpur (or a number of other cities in South-east Asia) for just 25,000 Mileage Plan Miles which should only cost you USD 493 (SGD 671) - that's two Business Class flights on JAL for under S$700!