There are a lot of different ways to produce joints from flat items, and not all are limited to laser cutters, but lots of the approaches carry around from fields like woodworking and metalworking. Mortise and tenon joints are similar to finger joints, except the "fingers" on just one piece https://bookmarkmiracle.com/story21773433/getting-my-second-hand-milling-machines-and-lathes-to-work