Ask HN: What do you guys use for IT asset management?

So a customer of mine is tracking racks and racks and racks of servers, switches, disks, ram, cards, and other things like their PCs, printers etc. all through spreadsheets and custom web app that someone wrote over 5 years ago which parses their excel sheet. They track this like location, status, warranty and other notes about each item. However, as you can imagine this current setup is a usability nightmare along with the obvious lack of scalability. I'm curious as to how other people track assets on a large-ish scale. I know there's some good software out there but many of their websites seem to have lots of marketing fluff making it hard to determine what is actually useful. What tool(s) do you use to do this?