Alain Schlesser is currently working on a project that detects when the “white screen of death” (WSOD) is being triggered by a parse error in a plugin. When this happens, the offending plugin will not be loaded on the login screen or the admin backend. Alain has submitted a Trac ticket for this feature, and the work that’s been done so far is worth a look. You can follow Alain’s updates on Twitter; here’s a good thread to start with.