We have an 18h layover coming up next Tues/Wed - arriving Sin from LHR at 0530 and heading to Syd at 0100 next morning. So for that extended time (because we changed our UK return dates and cudnt get a better connx) we will leave our thru-checked bags and head to the Crowne Plaza with just a carry-on of shorts, swimmers etc. It took a bit to get an agreement with CP on a day-use room (had to email an enqy and negotiate from there) but day use fills much of the time, plus a wander around Jewel, maybe a terminal circumnavigation, and of course dinner in TPR, should see us out to boarding time to Syd.