{"id":47045,"date":"2026-10-11T09:00:00","date_gmt":"2026-10-11T16:00:00","guid":{"rendered":"https:\/\/kk.org\/cooltools\/?p=47045"},"modified":"2026-10-09T08:46:52","modified_gmt":"2026-10-09T15:46:52","slug":"jurassic-sounds-free-utilities-china-travel-tip","status":"publish","type":"post","link":"https:\/\/kk.org\/cooltools\/jurassic-sounds-free-utilities-china-travel-tip\/","title":{"rendered":"Jurassic sounds \/ Free Utilities \/ China travel tip"},"content":{"rendered":"\n

Listen to a Jurassic forest<\/strong><\/h3>\n\n\n\n

Scientists have reconstructed what a Jurassic forest might have sounded like<\/a> 165 million years ago, and the one-minute audio is a really cool soundscape to imaginatively step into. They created it by analyzing and modeling the sound-producing structures preserved in 20 fossil insect wings from nine species that lived together in what is now Inner Mongolia. It\u2019s a diverse chorus of low trills and high-pitched chirps, and I wish I could loop it all day as background noise. \u2014 CD<\/p>\n\n\n\n

Inexpensive exercise headphones<\/strong><\/h3>\n\n\n\n

If I’m doing vigorous exercise, my earbuds fall out. I didn’t want to spend a lot of money on a second pair, so I bought these inexpensive Joywise Bluetooth headphones<\/a>. They are wireless, have loops that fit around the ear, and are connected to each other with a wire. Unlike most small earbuds, they charge via USB-C directly rather than in a case. The sound quality is great for the sub-$20 price, and the batteries last up to 16 hours before needing a recharge. \u2014 MF<\/p>\n\n\n\n

Analog math<\/strong><\/h3>\n\n\n\n

For mathematical nerds, Henry Segerman<\/a> is your channel. Segerman 3D-prints weird mathematical shapes, invents curious mathematical toys, constructs intricate mathematical models, and turns math into analog things you can 3D-print yourself. His YouTube channel demos all this with expert explanations of the math behind it. \u2014 KK<\/p>\n\n\n\n

Free online utilities<\/strong><\/h3>\n\n\n\n

Normal Tools<\/a> is a free collection of 193 single-purpose tools for all kinds of random small tasks, including calculators, color pickers, image resizing, and file conversion. It has more tools than I will ever need, but useful to bookmark. Most tools are private by default and process everything locally in your browser, with no account or download required. \u2014 CD<\/p>\n\n\n\n

China Travel<\/strong><\/h3>\n\n\n\n

I am traveling in China again and I am reminded that the best way for foreigners to book hotels, trains, and flights anywhere within China is to use Trip.com<\/a>. It is easy to use, comprehensive, accurate, and reliable. \u2014 KK<\/p>\n\n\n\n

The White Rose<\/strong><\/h3>\n\n\n\n

Besides Recomendo, Cool Tools publishes a newsletter about books called Book Freak<\/a>. I’ve been doing it for quite a few years, and I recently started finding old out-of-print books, scanning them, and turning them into ebooks with a new foreword and cover. This is a benefit for paid subscribers, and so far the library includes four books, with a new one coming every month. The latest is The White Rose<\/em> by B. Traven, who also wrote The Treasure of the Sierra Madre<\/em>. It was translated into English in 1979 but is out of print, so I used AI to translate the German version. It’s very readable and a fantastic book. You can read about it here<\/a>. \u2014MF<\/p>\n\n\n\n

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This Issue\u2019s Sponsor<\/strong><\/h3>\n\n\n\n

Why do smart people miss the future?<\/strong> Dev Patnaik explains why smart, hardworking people still get blindsided by change, and how to get better at noticing what\u2019s coming before it arrives. Watch the TEDx talk<\/a>.<\/p>\n\n\n\n

\n\n\n\n

Sign up here<\/a>\u00a0to get Recomendo a week early in your inbox.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Recomendo – issue #535<\/p>\n","protected":false},"author":47588,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0},"categories":[2323],"tags":[2324],"acf":[],"_links":{"self":[{"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/posts\/47045"}],"collection":[{"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/users\/47588"}],"replies":[{"embeddable":true,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/comments?post=47045"}],"version-history":[{"count":1,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/posts\/47045\/revisions"}],"predecessor-version":[{"id":47046,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/posts\/47045\/revisions\/47046"}],"wp:attachment":[{"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/media?parent=47045"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/categories?post=47045"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kk.org\/cooltools\/wp-json\/wp\/v2\/tags?post=47045"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}