I am a fan of slip joints. The development of slip joints goes back centuries. Some of the best makers of this genre are [IMHO] and in no particular order Tony & Reese Bose, Mike Zscherny, Jerry Halfrich, Bill Ruple, Joel Chamblin, Terry Davis. Here are some pictures to enjoy;
Tony Bose Lanny's clip with Oosik handles
Tony Bose Muskrat MOP handles & Gold pins
Tony Bose Saddlehorn Stag handles
Mike Zscherny Amber Stag Backpocket
Bill Ruple Splitback Whittler with antique tortoise handles and gold pins
Bret Dowell Dogleg Jack with pre ban elephant ivory handles
Jerry Halfrich Lanny's Clip with pre ban elephant ivory handles
Jerry Halfrich Saddlehorn with pre ban ivory elephant handles
Jerry Halfrich Stag Rounder
Jerry Halfrich Bose pattern wharncliff trapper with stag handles
Mike Zscherny amber stag trapper