Image Tuner is a free software for batch resizing, converting, watermarking and renaming your digital photos and images from and to JPG, BMP, PNG, TIF and GIF formats. The program will help you to prepare your digital photos to upload and publish them in the Internet or send via e-mail. It can be used to perform a basic set of operations that include batch resizing, converting, watermarking and renaming digital photos and images. 

Features:

• 100% Freeware. No spyware, adware, banners etc.
• Resize, rename, watermark and convert images in batch mode
• The most fastest image resizing algorithm
• Supports JPEG, PNG, GIF, TIFF, and BMP formats
• Variable options and settings for advanced users
• Built-in size templates: iPod, iPhone, Facebook, Twitter, DVD etc.
• Configurable compression / resolution ratio
• Load / save settings and image lists
• Clean, easy to use interface
• Small installation file ~ 2MB
• Supports Windows 98/ME/NT/2000/XP/Vista/7 (32 and 64 bit)

Home Page. (UPDATE: Based on the comments, it appears that it contains the Ask.com toolbar. So please make sure that you uncheck the options to install it)