I currently have 4 systems.
Main 2 channel system (posted on Audiogon).
HT 5.1 channel system - Rotel pre-amp, Rotel 5 channel power amp, Velodyne sub, Oppo Blu-Ray player, Wharfdale towers, center channel, and bookshelf surrounds.
Secondary 2 channel system - Rotel Integrated, Linn Ninka towers, Oppo DVD, Cambridge Audio DAC
Office / Computer system - Marantz DAC / Headphone amp, Klipsch “the Fives” powered speakers, Beyerdynamic Headphones.
I rarely get rid of old gear and repurpose them in other systems elsewhere.