WILL A HEART RATE MONITOR RECORD CONTINUOUSLY?

Hello,

I am wondering if a "heart rate monitor" will
record a workout that lasts about 3 hours long?

Someone told me you can have the information
go straight to your computer in real time,
and that "Polar" makes a device for this?

I am not talking about the watch recording
a few strands of data, but I'm talking about
an actual connection to a computer that will
record every few seconds what my heart beat
is.

Does anyone know if this is true? Any comments
or help most appreciated.

Thankyou.