Aside from writing about investment banking topics, the Bankers Ball website has a good series of articles with Blackberry help as well.
Here are some tips for filtering your inbox. These are particularly useful if you have a lot of sent items cluttering things up.
Alt + I = filter by Incoming messages only
Alt + O = filter by Outgoing messages only
Alt + P = filter by Phone calls
Alt + V = filter by Voicemails
Alt + S = filter by Text Messages (SMS)
Here's a link to the article.
Any other good filters or blackberry help tips that you use?