I frequently have to deal with requests from users. Over time I've come up with a four part method of deciding if I should classify a request as a 'project' and put it through the project management process, or a 'task' that I can do without too much ceremony. After some creative brainstorming I even came up with an acronym. It's not a project if its SLIM
Short Time. It will take less than two hours.
Limited Parties. Not more than 2 other people involved.
No Process Impact. It won't change how an existing process works (no training or user doc , etc)
Mostly Self Contained. It won't require a lot of interaction with other program and data flows, data in or out does not need to be changed.
What types of 'personal' rules-of-thumb do you have to organize your time ?