Return the pagetitle from the resource with id 123: [[#123.pagetitle]]
Return the introtext of a parent of a current resource and display description for empty one:
[[#[[*parent]].introtext:default=[[#[[*parent]].description]]
]]
Or, more efficiently (see this MODX blog article):
[[[[#[[*parent]].introtext:default=#[[*parent]].description
]]]]
Return the content of the resources in rowTpl chunk while Wayfinder usage: [[#[[+wf.docid]].content]]
Return TV image from the resource with id 10: [[#10.tv.image]]
Return property articlesPerPage from the resource with id 1 of custom resource type Articles [[#1.properties.articles.articlesPerPage]]
Return the value of $_POST['myVar']: [[!#post.myVar]]