Since SmokinPRanch posted his field shooters' rest, I have a few easy builds that work well & a bit more compact.
There are (3)types: Bench rest for sand bags, fully adjustable for elevation & leg adjustment. Chair rest(BYOC) for those needing a bit of comfort, telescoping aluminum tubing. Combination bench/field rest w/belt clip, light & handy, (2) heights for sitting or prone, fully adjustable for height, removable bench plate for field use.
Hope some of you may get a few ideas or modification to suit you.....