Using this extension, you can easily configure and add widgets to a Bolt website. This can be done both in the 'frontend' as well as in the backend.
This allows you to define specific 'blocks' for your website that don't really fit into anything else, or you can use it to render and cache parts of the page that are slowing down the performance. By adding these as a 'cached' or 'deferred' widget, the page will no longer slow down while waiting for all of the content to render.
bobdenotter/gridfield
This extension allows you to add a gridfield to your contenttypes, that you can use to quickly add tabular data.