This would make a lovely mod.
A Personal Library would collect all the threads and optionally specific posts I find the most useful or delightful. Perhaps also priority Follows.
With a Personal Library I can Like a post but also if I want I can save it to my Library. (Saving all Likes wouldn't work because many Likes are just temporary, friendly gestures.)
My Library stores my selection of Posts which I find particularly useful or delightful. For example on this board I would save to my Library certain posts describing workarounds; tips and tricks for using a feature or add-on, a helpful link to another site. Plus a few purely enjoyable favourites.
At the moment (and on the previous forum sites both .com and .org) I keep an external document that I paste in the URL of such posts, labelling them to make sense to me. It would be much more appropriate to keep that kind of personal record on the board itself.
We do have a list of watched threads. But many threads are long and then there are certain particularly useful posts buried in them. Also I don't want the chore of culling my old Watched threads, nor do I want to trudge through them to find what I need - plus then scrolling through loads of pages to find the specific post. Having a Personal Library of selected posts has obvious advantages.
I SUGGEST THAT a "Library" link appear by "Like"
and a link to open my Library appear with the list of links under my name at the top.
Then on the Library page itself I want to select out certain priority favourites to Stick at the top of the list.
I want to be able to Sort and Search the list.
My Library page needs a link to Watched threads.
I want my list of Watched threads to each have an Add to Library link as sometimes I want the whole thread e.g. about a favourite add-on.
My Library page could also possibly integrate Follows too, selecting my most important ones, or optionally all.
This would obviously be especially useful to board mods / admins for entering links to useful posts. But also for people's feeling that they have a personalised home of resources to hand.