Why does someone needs 20 different scopes/multimeters/power supplies?
It does sadden me when I see pictures of peoples' labs, and they're piled high with old equipment. Space has value, and if you have £500 worth of equipment taking up £5000 worth of room, you'd be much better off with a single £5000 instrument taking up £500 worth of room.
If that's not an option, a single £100 instrument taking up £1000 in space is still a better choice if it does 80% of what you need. Find something else to do instead of the other 20%. Go read a book, take up a sport, walk the dog, whatever.
I freely admit I have too much equipment, though in my defence I make a living doing this stuff, so having some spares is no bad thing. "Sorry, I can't complete your project because my scope is out for repair" is not an acceptable thing to say to a customer.
Where I do save on room is by being ruthless about storing things. Once a project is complete, everything goes to the customer or the shredder. Notes are scanned, boards and any spare parts are sent back.
That 8 year old laptop in the cupboard really isn't earning its keep. Nor are the UHF or SCART cables, or your old 802.11b access point, the file server you replaced 5 years ago for being too slow even then, that crackly old phone, the extra long VGA extension cord or the speaker leads from the stereo you had as a student.
Put the vintage computer on Ebay. Keep one old PATA hard drive, not five.
If its batteries won't hold a charge, you probably don't use it often enough to care.
Scrap that old thing, but keep the box. It's nicer than the one the cat sleeps in, and he'll appreciate the upgrade.
*Nothing* still uses that connector.
Those data books belong in a museum, where nobody will read them. Not on your shelf, where nobody reads them, taking up your space.
Your TV has that built in now. They all do. You don't need a separate one any more.
Or its remote.
Or its power supply.
Yes, I *have* just been through a box of junk while I've been writing this, and marked half of it to go down the tip. It's been quite therapeutic.