ee Electric Eyes Image Display Program gqview GQView Image Display Program gimp GNU Image Manipulation Program xsane Scanner Program xpaint X Painting Application gtv Gtv Mpeg Player
For sound there are a lot of applications. Here are a few:
xmms XMMS Sound Player mikmod Player for .mod, .s3m, xm, etc. mpg123 Audio MPEG player gmix Audio Mixer xplaycd CD Player
Like other Operating Systems you can find and install other multimedia applications.