Giustino Borzacchiello

This plugin will show stats about your posts after your content.
Currently it shows:
<ul>
<li>Word count</li>
<li>Characters count</li>
<li>Reading time</li>
<li>Speaking time</li>
</ul>

Postats

This plugin gives some statistics about your posts (word count, etc.)

eroux

Supplying an <a href="https://en.wikipedia.org/wiki/International_Standard_Book_Number" rel="nofollow ugc">ISBN</a> (and, optionally, a Title) will display a cover image of the relevant book with a link to that book’s page on <a href="https://books.google.co.za/" rel="nofollow ugc">Google Books</a> using the Google Books API.
Using the Widget you can choose whether to:
<ul>
<li>Force all calls to Google to be HTTPS, instead of the API returned HTTP</li>
<li>Pad the Image (selected by default, uses internal CSS)</li>
<li>Display a Box-Shadow (selected by default, uses internal CSS)</li>
<li>Choose Alternate Google Country (defaults to “Worldwide”)</li>
</ul>
as well as
<ul>
<li>Decide whether you would like to use a Title</li>
<li>Define the ISBN-10 or ISBN-13 of the book.</li>
</ul>
<h3>Usage</h3>
<ol>
<li>Activate the Plugin via “Plugins” → “Currently Reading” → “Activate” (if you hadn’t already done so).</li>
<li>Go to “Appearance” → “Widgets” and drag the “Reading” widget into whichever Sidebar you choose.</li>
<li>In the “Currently Reading” widget, you can then customise it further.</li>
</ol>

Currently Reading

Displays a cover image of a book with a link to Google Books based on a supplied ISBN-10 or ISBN-13.

Postats vs Currently Reading