I use
Amazon.com: 500g X 0.01g Digital Scale 0.01 Gram Precision Scale for Jewelry Coins Reload By Bubble Star. It has a fairly long time before it shuts off, though my practice on one that didn't taught me to always finish an ingredient so I can just tare it out if it does shut off. It also has a relatively large platform which is handy for those of us with an extra klutz gene.
I started with
http://smile.amazon.com/gp/product/B0026KXU7W/ref=oh_aui_search_detailpage?ie=UTF8&psc=1, but I had looked at enough scales that evening that I managed to miss that it had a .1 g accuracy instead of .01 and it also has a very fast auto shut off, so I do not recommend it.
I know that one is supposed to get calibration weights (also available at Amazon) but since I'm more interested in reproduction than I am in pin point accuracy I haven't gotten around to it yet. Reading Amazon
reviews you do want to be sure you know what calibration weights you need for a particular scale, since quite a few people seem to have gotten the wrong ones. Another advantage to procrastination, since the manual that comes with the scale will specify what size(s) you need.
Just another plug for the wonders of weighing - I find it a lot easier to drip flavors in until I get to the right weight than I did to get just the right amount into syringes. I still use syringes to transfer some ingredients, but I don't have to keep fiddling with pulling up the exact amount.