Packt is having a Columbus day sale. Every e-book and videos are 50% off. The sale has been extended through Monday, October 21. It’d be a great opportunity to get an e-book of WordPress Multisite Administration while it’s half off. You could get it for $8.50 using the promo code COL50.
All Packt e-books and videos are on sale for 50% off, so chances are pretty good that you could find something you’d get some use out of. I wrote more about what books you can find over at Medium.com.