Our band keeps a "black book" that get's passed around rehearsal. Members tick which engagements they will be at and which they will not (usually leaving a comment as to why not). Because it is paper and pencil, they are able to change their availability if some frees up or comes up. Members are also expected to tick which rehearsals they will not be at ahead of time, and leave a comment as to why not. For the most part it works quite well, except when things come up on short notice as we only rehearse once a week. Can anybody think of a way to transfer this to an online format? Would it be possible to password protect it in a manner so that all band members could see who is available but only update their own status?