IrfanView is a free image viewer and converter that supports an extensive list of formats.

Supported file types include:

AIF, ANI/CUR, ASF, AU/SND, AVI, B3D, BMP/DIB, CAM (Casio JPG), CLP, DDS, Dicom/ACR, DJVU, ECW, EMF/WMF, EPS, FlashPix (FPX), FSH, G3, GIF, ICO/ICL/EXE/DLL, IFF/LBM, IMG (GEM), JPG2000, JPG, JPM, KDC, LDF, LWF, MED, MID/RMI, MNG/JNG, MOV, MP3, MPG, MrSID, NLM/NOL/NGG, OGG, PBM/PGM/PPM, PCX/DCX, PhotoCD, PNG, PSD, PSP, RAS/SUN, RAW, Real Audio (RA), RLE, SFF, SFW, SGI/RGB, SWF (Flash/Shockwave), TGA, TIF, TTF, TXT, WAD, WAV, WBMP, WBZ/WBC, XBM, XPM, CRW, NEF, ORF, RAF, MRW, DCR, DXF, MOV, QTIF, Mac PICT, FLI/FLC.

Some features of IrfanView:

Multi language support, thumbnail option, preview option, slideshow, drag-and-drop support, fast directory view, batch conversion, e-mail option, audio CD player, print option, change color depth, scan support, cut/crop, IPTC edit, effects (sharpen, blur, Adobe Photoshop filters), capturing, extract icons from EXE/DLL/ICLs, lossless JPG rotation, EXE/SCR creation, many hotkeys, many command line options, many plug-ins.