Most of my lists are kept on paper. Some of their @-contexts are more generic than others. For example:

• @Online lists everything I just need plain internet access for. I could do this in an internet café.
• @Home also lists online-todos, but only those I need to do at home. E.g., when I need documents I can't (or would not want) to carry with me.
• @Office also lists online-todos, but only those I need to work on in the office (Most of the time, I need additional reference material here that my clients won't allow me to take out of their offices).

As you can see immediately, some contexts imply others - @Home I'm also @Online, and @Office I'm @Online, too. There is a danger here: if I looked only at the @Home list while I'm at home, and in the office only at the @Office list, I'd risk to forget that I could finish some @Online todos at home or in the office as well.

For that reason, I keep the more generic lists (like @Online) on top of my list stack. That way, I see them first when I look at the stack.