SQL Skills has presented what I personally feel is one of the best 30 Day checkups any MS SQL DBA can go through. The information in each of these days is well explained with great examples and is crucial for any DBA to have handy.
For myself, I have been using this as a skills checklist to make sure I’m at least up to par with an accidental DBA. I would also like to direct special attention to Day 20 where Kimberly Tripp goes over indexing. Indexing is by far one of the more important skills for any DBA or DBD to have. Creating quality indexes, maintaining them and making sure queries are using them properly can easily make or break a database server and application. In Day 20, Kimberly does an excellent job at presenting what to do with Similar or Semi Redundant indexes. This is probably the best, and easiest to understand example found anywhere on the internet.
Hats off to you Kimberly