Here's one idea... definitely don't take any data that could be construed as belonging to your employer, but if you develop a solution, there's no reason you can't keep a database of things like that. Especially stored procedures, functions etc, or a general design.

Create a database on your personal computer and if you're allowed (check first), script out the structure of the tables you need and the stored procedures, etc. Then fill them with fake data. Jeff Moden has a routine somewhere around here that generates something like a million rows of data (look for "JBMTest"). Modify that to insert the proper data types into your tables.

Then you can create stored procedures and reports based on that. I did one for fake patient data where I found the top 200 most frequent first names and last names, and then did a top values/cross join to populate a table with fake people. Birthdates are easy - generate a random number and use DATEADD() to make it look reasonably realistic. (If you have The Guru's Guide to T-SQL, the author gives a bunch of examples of creating stored procedures to crank out fake data.) Then write all your stored procedures etc for your reports and away you go. Sure, the data is fake, but who cares?