Everyone’s aspect is different. Depending upon site everybody wants to customize by his/her choice or different ways. Suppose you may like to show recent and popular posts in the sidebar somebody would like to show random posts with few his/her chosen specific posts in the sidebar. Like i’m showing only few recent published posts in my sidebar with customize recent post plugin.
WordPress Plugin to Show Posts in Sidebar Based on Tags, Author, & Category
Here is a cool wordpress plugin named Posts in Sidebar which creates a new widget for your sidebar. In this widget you can display a list of post from a given author and/or category and/or tag. You can also display the featured image, the tags and also a link to the archive page. A bunch of useful options are also available.