Allsop

Hmm, One way I can think of doing this with minimal effort:
 
Create a new blank workflow.
Add a Hotkey Trigger, and set the hotkey to whatever you want.
Add an Action "Run Script" leave everything default (/bin/bash) and paste the following in the Script area:
 
date "+%y-%m-%d"
 
Then drag a connector from the right edge of the Hotkey box to the Run Script box
 
Now, add an Output "Copy to Clipboard" and in the blank box put:
 
{query}
 
then select "Automatically paste to front most app"
 
Now, drag a connector from the Run Script box to the Copy to Clipboard box.
 
and save
 
NOW, when you hit your hotkey combo, the date in format {y-m-d} will be pasted wherever your cursor was last.

You can persist the clipboard for up to three months, where Alfred will save every item copied to the clipboard. You can then search by typing part of the copied text.
 
As for scrolling through without narrowing your search first, Alfred shows you 50 items by default, so just use the down arrow to scroll through these

This is a bit of an aside - let me take off the Alfred hat and put on the professor hat for a minute....
 
I wouldn't go near DevonThink - it's overkill for bibliographies on one hand, and it doesn't have the library/database integration that dedicated bibliographic software has.
 
But I'd also never try to manage PDFs just with the file system.  I have about 5000 PDFs indexed in a library in BibDesk (even though I don't write in BibTeX) that originally began 20 years ago as a 400-item Paradox database (in the days of WordPerfect) when I was a 1st year grad. student.  If you are serious about an academic career, you should be using some bibliographic management software -- if I were to start now, I might do it in Zotero rather than BibDesk but the formats are generally exportable/importable relatively easily (see http://en.wikipedia.org/wiki/Comparison_of_reference_management_software ).  The sooner you start doing it, the better - right now you may have one list that you want to maintain of things to read, but soon enough you will have lists by courses you are taking and/or teaching, for comps, for research proposals, articles, thesis, second book, etc.  And a lot of your PDFs are going to belong in more than one of those places.  If you're annotating your PDFs, you don't want multiple copies...so you can create aliases (and now tags, which helps but doesn't solve all the problems) in the file system.
 
So for keeping a reading list -- my BibDesk library at the moment has about 10 static folders titled "_current.project_name" for various articles and book chapters.  Each of those has the full biblio for the selected project.  Publications are tagged "to read" if I haven't read them.  So depending on the project I am working on, I can filter the project biblio by the tag "to read."  And this is all exposed to Applescript (one of the great things about BibDesk).  So -- say you have set up a smart group for all of the publications you have added in the last month, and those are what you want to be reading from -- you could put this script in an Alfred workflow:
 
tell application "BibDesk"
 
activate
 
tell document 1
select group "added in last month"
select (search for "to read")
end tell
end tell
 
and it would automatically give you your reading list.  Yes, you could do this with smart folders and Mavericks tags, but when the day comes that you want to write and cite some of the documents you've been reading, having it all indexed in biblio. software will make it much less painless.  Especially if you are submitting to journals with different citation formats.  It may seem like more work up front, but Google Scholar and all of the big academic databases let you download the citation info.  If I am going to read something related to my research, chances are it's worth being able to find it again, so it's worth the minute or two that it takes to get it into the database up front.  Just start with what you are currently reading, then you can catch up on the rest later.
 
Also...looking at your 1st post - with BibDesk at least the PDF files can remain exactly where they are, and you can set it up to auto file new PDFs according to a customizable naming convention - mine are filed in folder by first letter of author's last name, then author date title.pdf .  So everything is still easily findable if you're not using your biblio software.
 
Anyway, there's my unsolicited advice - same advice I give my grad. students - the long-term payoff is greater & the work is less the sooner in your career you start using biblio. software.

Allsop, thanks for your thoughts. Maybe you are right and I should spent some more time getting used to DevonThink. 
 
Vitor, that is perfect! This is what I was looking for. Many, many thanks!! Is is not that I am looking for a tool to set up a list of 50+ documents that I need to read, it is more like 5-10 in the near future or for a specific chapter/section, though your workflow looks very much of help! Thanks! 
 
@Vitor: It would be great, if possible, to allow quick look (pressing shift) within the workflow. Not sure if this is possible. 

Sounds like you're all up and running but here are two tutorials you might still find useful:
 
The first is on installing and setting up existing workflows. For example, when you import a new workflow, you'll need to set your own hotkeys and this tutorial walks you through how to do this.
http://blog.alfredapp.com/2014/04/02/tutorial-importing-and-setting-up-alfred-workflows/
 
The second one will show you how to create your first workflow. Once you understand how to connect workflow objects together and trigger them with keywords and hotkeys, you'll be able to create almost anything.
http://blog.alfredapp.com/2014/04/24/tutorial-creating-an-alfred-workflow-without-a-single-line-of-code/
 
Don't hesitate to post in this section of the forum if you're trying to create a workflow and have questions. It's filled with loads of very lovely and helpful people
 
Enjoy!
Vero