Can I come dig through your scrap iron box at work?:gar-Bi I'm going to guess that someone else is throwing away good things because they hate the place/boss. That steady rest will bring $150 on EBAY and would probably cost your company $300-400 to buy new. It probably fits a 14"-16" or so lathe. Looks similar to the one I have on my 14" lathe.
Keep an eye on the scrap box. Anything you don't know what it is take home.
If you want to be a good guy go find where they run the lathes at work and see if they are missing a steady rest. Also be careful someone isn't setting you up and going to accuse you of stealing.
Only a #$%@ would throw something like that away.