Whenever you are soliciting donations from industry, always make the donor feel that you are extremely grateful. It is the job of every educational institution to ensure that their contributors feel appreciated and that they are not sending their money down a black hole.
Make it Visible: Place placards or signs on donated equipment and material stating who donated it and when. Always keep the area around the equipment clean and professional looking to demonstrate respect. If a piece of equipment is no longer needed, offer it back to the company before taking it off display (they might offer you something useful in exchange).
Show Your Appreciation: Give the donor a placard, certificate, etc. that they can display in their lobby or conference room. This keeps your institution in their minds and gives the added benefit of others becoming aware of your institution. If this is dated, it will prompt the donor to keep their placards up-to-date.
Spread the Word: When possible, get the contribution written up in either in a paper or on a website. You should also have a special section on your website where all donors are featured. This will give exposure as well as create some potential competition between donors.