Very well done map detailing the locations of the collectibles. It contains all of the Stunt Jumps, space, Spaceship Parts, and Letter Scraps. Most of the others will most likely be included this week at some point.
You can click on individual locations and a video will pop up showing the items location and you can check them off as you find them. The videos are extremely helpful because it zooms in on the exact location on the map, so you can see where to set a waypoint.
I have about an 80% game completion so this is how my time in GTA is being spent right now.