Well, each of these systems I COULD write myself, like any decent Blitz developer should be able to do. But then there is the choice if you WANT to code it yourself or save time by buying it. For me, the fun comes with coding stuff so I decided to code all my tools and systems myself. Other people just want to go ahead and start on a game, which is why most of us bought Blitz for in the first place. Don't be a jerk and state the obvious by saying you can code it yourself and therefore another person's effort mean nothing at all because, frankly, that is not true. A lot of code which makes up these tools appear in the Code Archives and are a great help for others do decide how to approach a certain problem... and that is invaluable.