Ask HN: How do you manage bookmarks?

I've a habit of hitting {Ctrl|Cmd}-D every time I see something interesting, with the intention of reading it later. Consequently, I've accumulated hundreds of bookmarks over the years across different browsers on different machines.

I imagine this must be a common problem, and a quick search reveals a plethora of tools out there for managing libraries of links. Does anyone have recommendations? Ideally it'd be either cross-platform software or SaaS without locking my collection into something proprietary.