I disabled my trashbin by default which means that deleted items bypass the trashbin and are deleted immediately. This works fine most of the time but it happens that I occasionally delete a file that I need later on again. There is no obvious way to get those files back and you will face serious troubles if want to get them back but used something like defragmentation on that hard drive after the deletion.
The question that some might ask is why one could recover deleted files at all. This is actually a very good question. Windows does not delete the file at all when you press the delete button. It simply deleted the reference to that file and makes the space the file occupied writable again. This means that you can recover most files if you are just fast enough. One freeware that can do the job is Recuva which is supposed to be pronounced recover.