There aren't unlimited tourist opportunities here, but there certainly is enough to keep a tourist busy for a few days. The people who say there isn't anything to do here have been here for long enough for all of the opportunities to get old or worn out. Either that or they are just bad-mouthing Qatar in general.

I would suggest leaving Doha and seeking out some of the cool waterfront areas around the country. It's a fun drive and you can get around the country in a day.