What to do when the maintainer has gone away?

Drupal is an awesome open source system, and the community around Drupal is great. There is a lot of very useful contrib modules. I have supplied several issues and some small patches to several projects, and most maintainers swiftly responds.

Other projects the maintainers are very busy, and that is quite understandable. However, for me to keep being interested in trying to help to improve some module, it is important that one is able to see some headway in a project. You actually want to see some of your improvements and bug fixes committed - which makes it easier to move on to the next improvement without your patches going stale.

Consider these examples:

• parser_ical. I filed a bug and provided a patch in January. I tried contacting the maintainers to get the patch included, but received no response. The module still stands as unsupported in the D7-version. I would like to help change that, but when the maintainers does not reply, it is difficult.
• media_gallery. We are a couple of people who has been trying to do a lot of the dirty work in the issue queue for media gallery. We have been closing issues, fixing small bugs, providing patches, trying to find a way to make it work with the 2.x-branch of media. But still there has been no response from any of the current maintainers. I tried through the issue tracker, IRC and through the contact form on d.o.

Both projects are really good and created by skilled people. And off course skilled people get busy, and do not have the time for exactly that project right now.

But how can the community solve this? It is very likely that people will just cease to provide bugfixes and help maintain an issue queue, if they can see no progress from their work.