Locomotive jacks.
Fullsize image: https://diqn32j8nouaz.cloudfront.net...s_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...tive_jacks.jpg
Previously:
https://www.homemadetools.net/forum/...004#post137757
https://www.homemadetools.net/forum/...066#post120458
https://www.homemadetools.net/forum/...084#post145231
https://www.homemadetools.net/forum/...967#post112043
https://www.homemadetools.net/forum/...724#post111399
https://www.homemadetools.net/forum/...685#post132986
https://www.homemadetools.net/forum/...527#post135971