Clustering Raspberry Pies Together

mayhor says that this is just for home use, and it's presumadly just for the fun of doing it. But is clustering raspberry pies together really a good idea for anything beyond a ba of fun? I think it's useful if you just want to learn, like, you know, youyo wnt to build a cluster. It's extremely cheap hardware that's not very reliable and kind of weird. And probably not actually getting more fault tolerance because you have such flaky hardware.