I know this is not exactly
high tech, but certainly it is “tech”.  Useful
new products that are Green – that is, battery powered using Lithium Ion batteries.  Cordless, gas-free, maintenance free. 
I ordered this B&D hedge
trimmer from Amazon, tested it this morning and am amazed, impressed that such
a tiny battery, only 20 V, Lithium Ion, can be so powerful. I gave out before
the battery did.  It is very light, and very
easy.  I highly recommend this if you
need a trimmer.
I also ordered a pole saw, to
cut limbs, and bushes.  This time I chose
GreenWorks, a new brand to me, but highly recommended on various websites.  It uses a much larger, heavier and more
powerful battery.  40 Volt.  It is beautiful to look at, and I am sure
will be very powerful based on many reviews on Amazon and other sites.  Take a look if you need a trimming tool, 10
inch chain saw at the end of an adjustable length stick, should be safe and
easy.
BOTTOM LINE --  battery powered lawn equipment has come a
long way, and I will probably never buy one with a cord or a gas engine again.