A person can do a credible job with 100 watts and a short, well tuned 
antenna.
When I worked 160 from Chicago I had never anything better than a 
trapped dipole, 100 or so feet long, with a loading/tuning network at 
the station end of the coax.  I suppose it was technically a top 
loaded, thirty foot vertical, but who knows.  I also had a couple of 
radials buried randomly under the antenna.  They couldn't have been 
more than a hundred feet in total and they were connected to my 
stations ground rod.
My best DX was San Francisco on CW at about 40 watts.  Made me pretty proud!!
It's a great band.
Pat, K9JAUAt 03:05 PM 1/27/2007, you wrote:
>Folks, I regularly work the arrl 160 contest and will be in the cqww
>tonight.  My antennas are as follows:
>1. 120 foot physical length dipole with 20 feet of loading near each
>end, and a drooping tail at each end.
>Amounts to 180 feet of wire in the air.  This is at approximately 25 feet.
>
>2. 90 foot half sloper fed against the 30 foot tower supporting the feedpoint.
>
>Neither of these are anything near optimal, but in the cw contests,
>do reasonably well.
>
>Good luck to all participants..
>
>
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