It's a simple request with a complicated solution: how can you display a list of nodes such that the first one is displayed in full, while the rest are displayed as teasers? For years, it's been possible to do that with the Views module by craftily combining two views: one for the first node, another for the remaining ones. While that approach gets points for craftiness, it's cumbersome and forces you to maintain two separate View displays. Thankfully, the newly-released Views Nodes Split module has made the trick simple.
Setting up the module is simple: just turn it on, and build your View as you normally would. Then, click on the View's Format option and select the newly available "Splited Content" row style. While the grammar is awkward, the results are great: you can specify separate build modes and display styles for the first node and all subsequent nodes from a simple config screen. In fact, you can even adjust where the cutoff happens: you might want the first three nodes to display in full, for example. No other changes are needed for your View; this module's new row style handles the rest.
Views Nodes Split is a great example of a simple module that does something useful, and does it well. If you've ever needed to build this sort of View for a front page, featured news, or other content listing, check it out!