Root Rescue by L’Oreal is a great solution to save money on hair expenses!  It keeps the salon-inspired color lasting a little longer!   (Psst, this is also an easy way to hide those evil grays! :) )  Check out this deal that I found at Walgreens:

Root Rescue by L’Oreal $4.49, On Clearance
Use $2.00/1 L’Oreal Root Rescue coupon found in store next to product
Final Price: $2.49