The three of us of bigbasstabs.com (the dude, kissy boy and myself) have come up with another website called musicdiscipline.com
It's a website that lets you enter the time you have to practice and then it gives you exercises one by one, and it remembers which ones it already gave to you, so that the next time you come, you get a new set of exercises.
Currently there are only exercises for guitar (as I am primarily a guitarist) and are all written by myself.
Of course, next on the list are bass exercises, and we've already started working on them so as soon as we're done writing we'll add them to the site as well.