The graphic image above represents the number "73" in Morse code. 73 is an old telegraph code that means "best regards". 73, as well as 88 (which means "hugs and kisses") are part of the language of ham radio.
The image should be flashing if your browser supports animated GIFs (Netscape Navigator 3 and Internet Explorer 4 should work well, Netscape 2 and Explorer 3 seems to have some problems getting the timing right). If your browser is displaying it correctly, a dot should flash for a tenth of a second, and a dash for three tenths of a second. The whole sequence should take about three seconds — if it does, its rate is about 12 words per minute.