lack of magnetic shielding and speakers near your computer

Unshielded speakers placed close to a CRT monitor (or television) will degrade the focus and color rendition of the monitor, due to magnetic interference. If the speakers are near the monitor long enough, the damage can be permanent.

Less common, but still a consideration, is that magnetic media, such as flash cards, floppies or video or audio tapes, can be degraded by exposure to an unshielded speaker's magnetic field, or the magnetic field given off by a monitor or TV - don't set magnetic media on a speaker, monitor, or TV.