Backup archives are IMHO underappreciated. Like these that I still have:

kite.04.aug.1999.disk.2.tar@ kite.1999.disk.2.tar@ kite.sep1999.disk.2.tar@
kite.04Aug1999.disk.1.tar@ kite.sep1999.disk.1.tar@ kite.sep1999.disk.3.tar@