These are harmless memory resident parasitic viruses. They copy themselves to Interrupt Vectors Table, hook INT 21h and write themselves to the beginning of COM files that are executed. The viruses do not manifest themselves in any way. "Sms.480" contains the text:
SmS bItEs !!! aNd Is gAy ToO !!!
wRiTteN bY BiGMaRtY, 2/13/96
HaPpY vAlEnTiNeS DaY eVeRyOnEall
tRy nOt tO fUcK tOo mUcH ;)
