B&H Photo-Video offers the Adobe Photoshop Lightroom 4 Student and Teacher Edition for Windows and Mac, model no. 65164859, for $55.99 with free shipping. That's tied with our expired mention from four days ago and the lowest total price we've ever seen. (It's a current price low by $2.) This program offers a variety of photo-editing tools.

Of note, you'll be required to submit proof of eligibility in order to unlock the software; click here for more information. (You'll be able to use the software in trial-mode for 30 days until you receive your serial number after providing the required proof.)