2GIF.EXE is a command-line utility which allows you to convert images from 15 popular formats into GIF.

You can convert to GIF format from BMP, DCX, DXF, EMF, EPS, FPX, GIF, IMG, JPG, PCD, PCX, PNG, Targa, TIFF, WPG, and WMF.

In addition, the program supports zooming and interlacing, and lets you perform conversions in batch mode. It comes with an image cropping tool.