At the University of Delaware, we support two Learning Management Systems. We have been running Sakai ever since Blackboard bought out WebCT, and now we have added Canvas. Migration to Canvas is entirely optional. We really are not pressuring people to choose Canvas over Sakai, so no one needs to give up what they know. On the other hand, we like to remove barriers, and one tool that Canvas has no counterpart for is the Sakai Post'Em tool.
Post'Em itself is a work-around for anyone dissatisfied with the Sakai gradebook. It is a very simple tool, which allows instructors to upload the contents of their Excel gradebook spreadsheet, and have individual rows presented securely to students. This by-passes any and all limitations with the gradebook itself. You can take advantage of the full power of Excel (or any other program exportable to .csv) in order to calculate grades. Some instructors on our campus who are otherwise ready and willing to try something new were hesitant to make the move to Canvas without having a Post'Em equivalent, so we took advantage of the Canvas LTI and API to build one.
Recently, we have received a request from Indiana University to share the code, which we have done, and no doubt they are by now well on their way to making it better.
This is not necessarily the best place to try to make a record of what has been done, but I did promise to do something on the new Canvas Community site to get some conversation going around the Post'Em effort. Since I wanted to figure out how blogging works on this site, I thought I'd just throw something out there and see what happens. I apologize if this is the wrong approach to take.