ClipCube, until very recently known as Clipbox, is a small and minimalist clipboard utility that keeps an unlimited (?), until recently up to 2000, number of clipboard items for future use. The program runs in the system tray. ClipCube lets the user decide how long it keeps clipboards on file, this is set by right clicking the program icon and choosing the Keep Items entry. The available options are keeping the item(s) until the program is exited to keeping them indefinitely. The program window or interface has settings for pinning or keeping it on top and also choosing to show a full preview of a selected clipboard item or not (by toggling the eye icon on or off). One other option is showing a time stamp beside each clipboard item, this lets a user know when the clipboard was captured.
ClipCube also supports hotkeys (see http://clipcube.wikispaces.com/Changelogs for a full list of hotkeys as they are added to each version) that ease program usage such as Enter+Ctrl+C to copy a selected clipboard item and Ctrl+Numpad[1-9] to choose the first to ninth entry in the listed clipboard history. The latter did not work in my test of the current version (0.2.2) and additionally brings up the question of how one may be able to choose the 10th, 11th or higher numbered items in the clipboard history list.
ClipCube is GPL licensed software and does not require installation. This program is in development and the interface and options have also changed recently so this review may be outdated in some respects by the time you read it.