I've given away a stand for a 75/90/110 gallon tank in the "free" section on CL, only to see it paired with a 75 and on sale a week later! Bad karma for the guy who picked it up, IMO.
Mostly smaller tanks, Random live bearer fry, cichlid fry, random fish I had gotten over the years. But mostly.. My knowledge. 2 family members are teachers. class fish tanks ect.. guess who gets called in to supervise stocking?.. lol I enjoy it though and love to see pictures of the kids enjoying the tanks. I was known as "miss dolittle" in my neiborhood growing up. I've prolly received as much as I've given away. TBH I don't even keep tabs anymore. To me it's just apart of the hobby.
a 750 gallons acrylic tank w/ a 150 sump plus the 4 feet shark that the set up was built for ,,,,I have yet to get a call from the bastard after he got the loot / //
I have given away quite a few things. Below are the things I can remember.
about 3 or 4 canister filters
roughly 30 fish ranging from platies to full grown oscars
6 complete setups
lights
stands
pumps
food