There are tens of thousands of public companies and just one of you. If you have a full-time job, you probably cannot afford to look under every stone for undervalued companies.Luckily, there are plenty of sources to give you some insights into interesting companies, so you don’t start from scratch. That doesn’t mean you should act upon the information below. You have to do your own due diligence; otherwise, you’re acting on borrowed conviction, which oftentimes ends badly.I hope you find some of it useful. Note: some of them are shorting certain public companies. Shorting is incredibly risky. I do think reading reports of this kind is useful for two reasons:If a company that you’ve invested in is covered, it gives you the arguments against your thesis.You might learn a new approach to analyzing a company that you can carry with you.Subscribe nowValue Investors Club (“VIC“) - Signing up with a valid e-mail address is needed to get access to the pitches with a 45-day delay. Yellowbrick - Not known by many, and whoever is behind it does a great job. Aggregates pitches and write-ups from funds, newsletters, and conferences into one feed.Stock Analysis Compilation - A newsletter compiling plenty of shared pitches every week.Greenhaven Road Capital - Small-cap focused, quarterly published reports, with short commentary on a few positions.Sohn Investment Conference - Pitches from managers, with the coverage being public afterwardMuddy Waters Research - Short reportsKerrisdale Capital - Plenty of investment reportsSubstack - If you have a few newsletters that you really like, have a look at the recommendations coming from those newsletters. Otherwise, you can always use the search feature and find analysts who cover what you’re looking for. Small cap, mid cap, European companies, Polish companies, Benelux-based, Nordic, Japanese, you name it; it is likely out there.Clark Street Value - A blog that covers special situationsReddit - There are a few interesting subreddits:SecurityAnalysisInvestingValueInvestingStocksUndervaluedStonksYet Another Value Podcast - Covering one pitch at a time, ~1-hour average video length.Dataroma - Great source if you want to see what the superinvestors are buying/sellingWhaleWisdom - Tracking 13F filingsStock screeners - I am not affiliated with any platform, and I think most do quite a good job and are offered in a free version. This offers a lot of room to experiment and drill down into public companies based on different metrics. If you’re creative (or have experience with screeners), you can find interesting companies to further look into within an hour. I might write a separate post on this, as it deserves more attention.52-week low lists - Plenty of websites offer this list for free; you can even do a deeper search by finding the 52-week lows in a specific country.Returns of the S&P500 companies - I always find it fascinating to see the big losers being down 50%+, given that these are, in some cases, $100B+ companies (market-cap-wise). This can be done over a longer timeframe; for example, the best- and worst-performing companies in the S&P 500 (or in a certain country) over the last 5 years.Stock spin-off investing - It has a stock spin-off calendarFriends and family (Peter Lynch style) - If there’s a product or service that many have adopted, it’s worth looking into it. This is quite a wide area, and all it takes is being observant about what’s going on around you.OpenInsider - Lots of insights into what the insiders are buying (although terrible UI)Once you stumble upon a pitch that is interesting enough, you can use X, Reddit, and Substack to see if there is more interesting research (whether tweets or really deep research) that can help you get a better initial understanding of the company. But don’t forget, it’s important that you do your own due diligence.What are your underrated sources for finding interesting ideas? Share them below.The Finance Corner is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber.