About two months ago, I went through a phase where I ran around trying to cross-pollinate everything that was in bloom: Chlorophytum, Nematanthus, Saintpaulia, Anthurium, Murraya. I'm not sure why. It seemed like a good idea at the time, I guess.
Mostly, this was useless. The possible Nematanthus fruit that I was so excited about dropped off without developing; the Saintpaulias weren't even willing to pretend that something had happened. The Murraya produced a few fruits, but I haven't been able to get any of the seeds to sprout; ditto for the Chlorophytum.
I thought that the Anthuriums were another case where nothing happened at all, and wasn't that surprised, because I had no idea how to cross them (it's not easy to tell when the flowers might be receptive; it's only barely obvious when they're shedding pollen), but it turns out that at least a few worked, as you can tell from the lumpiness developing in the spadices:
As for how I did it: I took a cheap plastic paintbrush and went around "painting" the spadices of all the Anthuriums then in bloom, in varying sequences, on multiple occasions. That's all. I'd tried other methods in the past (both rubbing spadices together and using fingers instead of a paintbrush), which never worked.
This doesn't mean I'm going to get seedlings out of this, and if I do, I won't know which plant was the male parent, but it does, at minimum, move me from the nothing-happened Saintpaulia category up to the something-happened-but-I-still-didn't-get-more-plants category. If I do get fruit and seeds from the Anthuriums, I'm fairly confident that I know what to do from there. Keep your fingers crossed for me.