We are all used to web searches giving suggestions of possible values you want and Combo Boxes have a Search function, but Text inputs do not have anything built-in for this, so it should be useful to have this function as well.
In the example below, the user starts typing and all matching values come up below. At any time they can press Enter and have the first (or only) matching value populate automatically in the Text Box.
The process involves only three things - changes to the OnChangeand Default of the Text box and a Label below. This example is from a test list I have, but will work on any list subject to size Delegation on the Distinct function in the Label (I am sure there are work-arounds if this is an issue).
Firstly, the OnChange of the example Text Box (txtManName) is