I have sailed boats with and without wind speed and or direction indicators.

On the boat I race on, we seem awfully dependent on instruments... to the point of constantly checking ever changing angles and doing calculations about favored sides and what not. (never seems to make a difference however... as the tactical moves seem to be far more important, as well as taking "one less tack," or getting a perfect start)

On my boat I only have water speed and depth instruments (and water temp). So I currently sail by the seat of my pants and the mast head windex. (I could use a few telltales) I can easily guess some wind speeds based on wave action... more than anything else I was thinking about a wind speed indicator just to confirm what I think I see. I could probably do this with a pocket instrument and avoid the whole hassle of drilling holes for anther instrument and running another line up the mast.

Charlie laid out a rather good argument for the instruments... but again I can pretty well guess when things are getting dicey... I guess I just wanted an actual number to go with my hunch. I am quite lucky in that I can easily light up my windex with my masthead anchor light... at least for brief looks.

True vrs apparent is another story... I am not even sure my old Datamarine instruments will give me the right data to feed a "modern" wind instrument. I'll have to dig around and see if there is any "data out" connection and what form that data is.

As far as cost, I found some stuff from Moor Electronics that is not quite in the boat buck range. Hence the "hey, maybe I do want this" thinking. Such thinking is quite fleeting however... as such things as new sails lean more heavily on the boat budget.