These snowless dry luges look like they’d be a great way to spend a day. You can race in groups, pass people, even crash and it appears that each location offers several courses to choose from.
Queenstown, NZ:

Sentosa Island, Singapore:

Mont Tremblant, Quebec City, Canada:

Canada Olympic Park, Calgary, AB:

Rotorua, NZ (crash!):

These have been around since 1966 but they’re new to me and added to my (ever-growing) bucket list.
http://www.skylineluge.com