I live in YQU and I must say first I am amazed you have any sort of layover here; mind specifying how you pulled that off? 90 mins is pretty short to do anything here though; I've lived here 8 years and I'm not sure I would even feel comfortable going to my house and back in that short of time. You could hire a cab for a 1 hour tour of town but I dare say you might be the first person ever to request that. If by some miracle your schedule made sense with mine I suppose I could run you around for an hour; I do love showing people the finer points of town but 90 mins is pushing it on the short side. If you can drink quickly there is The Shark Club downtown GP about 10-15 mins from the airport that was voted Canada's best sports bar back-to-back years in 2007 and 2008. You might have time for one beer if you keep the cabbie outside and the meter running. Failing that the Diamonds strip club is closer to the airport and you could always get a couple dances in. If you golf check out the mini golf course in Muskoseepie Park in the middle of town for a quick 18 holes and a "Screamer" a local delicacy consisting of vanilla soft serve and slush puppy mixed together. If you're hungry and I mean you should call ahead and place your order there's Better Than Fred's downtown that has amazing southern-style BBQ. Try the Jar-B-Cue served in a mason jar. Well those are my best suggestions but if you have 90 mins between arrival and departure that gives you about 45 mins to actually do anything as all of those options are 10-ish mins each way by cab and you want to be back at least 20 mins before the flight. Good luck!