Attaching a pager or phone type vibrator to this seeder would make it work much better as the seeds would bounce around and create a more fluid flow out of the spout.
Scavenging an old pager or phone for a vibrator/motor would be a pain, but I found an essentially free and easy alternative. A disposable vibrating toothbrush. The one I used was an oral b pulsar, but there are other generic brands out there. If you buy one of these, you will find out the battery doesn't last as long as the bristles. But they don't make the batteries easy to replace. Once you figure out how to replace the batteries without ruining the toothbrush, it lasts a lot longer. After the brush is toast you can use the vibrating motors for nifty little projects like this.