Small brackets come in handy for various uses. I used them to stiffen the legs on an IKEA Lack table. They are pretty effective while being unobtrusive. The bigger you scale them the better they will work. I think the scale I uploaded them at is about the smallest you can make them and still have them be of any use.
Check out these other things for IKEA Lack table...
Stacking leg couplers: https://www.thingiverse.com/thing:3488697
Table leg levelers: https://www.thingiverse.com/thing:3495732
corner_table_brackets_v6.stl | 58.8KB |