A checklist can be as simple as an spread sheet, so you could use:

-A shared network- or Dropbox folder containing Excel sheets

-A google docs account with check list spreadsheets

-Smartsheet.com

-Any wiki software, self-hosted or managed, i.e. wikidot etc.

-Any of the myriad of todo-list apps, just be sure the todo-lists (actually checklists) can be re-used as templates.

I also think in this case the simpler the better. GitHub pages is pretty nice solution. +100 to Google Docs too!