The file removal utility that can delete items ... later.
Native on Mac OS X.
Try now, buy later:

(v4.2, 1.3 MB, $6)
TrashLater
Shareware $6
(50% off from $12)
Version 4.2
Build 339
16 March 2011
Language: English
Requires Mac OS X v10.4 or later.
Universal Binary (PPC and Intel)
1.7 MB HD space
v4.2 (1.3 MB)
v4.1 (1.4 MB)
v4.0 (1.3 MB)
v3.5 (468 KB)
If your browser refuses to download .dmg files, use (something like) "right-click" save-linked-target-as.
Also available: versions for Mac OS 7-9.
TrashLater now runs all checks completely in the background.
Manage a download folder
It may be a good idea not to delete the .tar, .dmg and .sit files straight away - just in case you might need them again. But since you want to get rid of them eventually, why not leave them in your download folder and instruct TrashLater to trash these files a few days later?
Manage backup folders
Many tools offer to save backup files in designated folders. Potentially, these folders can grow quite large and should be cleaned out once in a while. Having said that, you never want to delete the most recent backups, so, why not let TrashLater trash only the older files?
(Hint: Reload this page for more examples)
What is TrashLater?
It is a file removal utility that enforces a grace period before the move takes place. Items can be moved to other folders or to the Trash.
During its operation, TrashLater watches over selected folders, keeping track on their contents. Any unmodified file that resides in a folder for longer than the grace period is removed. Modified files are regarded as new files.
How do I use TrashLater?
You use the TrashLater application to specify which folders to watch and their grace period. Even the Trash itself can be watched. Note that you can use different grace periods for each of these folders.
Next, you select a time interval for the checking. That is all. Save your settings and quit the TrashLater application.
A client process will check whether any files were in these folders longer than requested. Any such "out-dated" file will be moved into the destination folder, for instance the Trash.
The client process will be launched through the Mac OS X built-in scheduling engine "launchd". No application needs to be kept running in the background.
For more information, see the description alongside the Screenshots
Beta: TrashLater Server
Beginning with version 4.2, TrashLater can also be run as a system daemon. In this server mode, the client process will run with system-level (root) access rights, allowing it to manage folders for all users.
Naturally, the server mode is ideal for system administrators that have to manage many user accounts, e.g. using Mac OS X Server. However, it works just as well on a single-user machine running a regular installation of Mac OS X.
In the current version, TrashLater Server requires the use of the Terminal application for its installation and configuration. After the 30-day evaluation period, it also requires a dedicated TrashLater Server license; the regular TrashLater license is not valid.
For more information, please check the last chapter in the TrashLater User Guide (included in the regular download image or as a separate download).