Tube testers

Transcendent Sound made an excellent tube tester kit; discontinued many years ago but if you can find a working unit used, I highly recommend it.

With that said, I hope to replace it with an Amplitrex unit, hopefully one day soon.

For a whole lot less money, this little fella looks pretty cool:
https://www.dos4ever.com/uTracer3/uTracer3_pag0.html

uTracer3 for $247 vs Amplitrex for $2760 (as of yesterday). I don't think it has anything to do with fun, simply budget. You pay a hefty premium for convenience.