Short description
Since quite some time, there a nice web-based document viewers available such as Virtual Viewer, Ajax Document Viewer or iPaper. Ajax-Document-Viewer e.g. supports over 200 different file formats and allows easy viewing and embedding of different "mimetypes". I would be nice, if there were an easy config option in wikiconfig.py where you can choose whether a certain item ("attachment on the attachment page" in Moin < 2.0) is rendered on the client-side ("in the browser") or server-side (with the web based document viewer).
This feature could be especially useful for Moin as intranet in companies (who buy one of the above solutions).
For normal wiki users (who do not care so much about the privacy and security issues of cloud computing) they could use the above services for free.
In the long run there might be also some similar open source projects available which allow for a tighter integration of web-based document viewers (and editors??) with Moin.