香港網絡大典 (Rough translation: The Hong Kong Internet Compendium)
Formal written Chinese, with slangy Cantonese mixed in; limited English
香港網絡大典 (Hēung góng móhng lok daaih dín) is your #1 destination for explanations of Hong Kong internet culture. Found a confusing Pikachu meme without context? You're covered. Keep encountering pop culture references to some dude named Edison Chen? Read on. For all those people digging into the meme-dense space that is LIHKG, this is a great resource.
香港網絡大典 is mostly written in formal written Chinese (as opposed to written colloquial Cantonese), meaning it should be accessible to most people literate in traditional characters (run it through a character converter if you desire simplified). If you do not read Chinese, you can try Google Translate, but the results may be interesting.
Because this is a Wiki, you are getting crowd-sourced information. That means there may be some inaccuracies from time to time, but overall the info conveys impressive depth. There are meme repositories, video clips, and plenty of other elements to help widen your exposure to a Hong Kong perspective on the World Wide Web.
For instance, check out the page on 大時代 (Daaih sìh doih; a.k.a The Greed of Man), one of the greatest television dramas ever (I am only slightly editorializing). Whereas the Wikipedia entry on the show will just talk about the synopsis, cast, etc., 香港網絡大典 is more concerned with the pop culture and meme implications of the show. Thus, we have a nice gallery of classic lines from famed actor Kong Ngai (江毅):
As well as some fun history about when the 2015 late-night rerun of the show (which prominently features a stock market crash) coincided with a drop in the Hang Seng, further confirming the "Ding Hai Effect/丁蟹效應":
Overall, 香港網絡大典 may not be the best tool for Cantonese beginners, but it is a great place to explore if you are eager for cultural context. If you want to be at the cutting edge of what is happening, I recommend the trending news page (新聞動態):
There you will find summaries of current events in Hong Kong with handy links to relevant reference pages. It is incredibly helpful if you are tracking timelines of Hong Kong social movements.