Can't make a lookup field read-only on page layout - if it's on a custom object

... because then the lookup field stops working on the UI: if you create a new record from the "New" button on the related list from the parent object, the lookup field won't be populated, as it would when it's not read-only.

This is just the way it is, and I haven't found an explicit reference in documentation on why that is, or even the behavior is there.  Please note that this is not the same for standard objects.  For instance, the Account Name field on Contact will still work - populating correctly - if it's made read-only on a page layout.

So if you're looking this direction for a simple way to discourage reparenting (like I did), stop. 

Adobe Acrobat - page operation pitfalls

Overall Acrobat is a polished tool for handling PDF files, other than being a little bloated (using 9.2 at this moment).  However I have a few pet peeves about it, especially for page action items under the Document menu. 

• Inserting/replacing pages with forms.  This is pretty common when updating the form page in a big file.  First of all, replacing is usually not a viable operation (would be the best if it were!), because the replaced form almost always has some peculiar issues, particularly with the form fields.  Often times they're out of whack from the intended configuration.  Inserting is less bad, but do keep in mind that form fields will get merged if the document already has some fields with the same names as in the inserted form.  It does remind you that when you try, but provides no option to help you remedy it - locating/listing the duplicate fields or something.
• Replacing pages with graphics.  I recently had an issue that if I replaced a page with a new page with graphics, the border around some of the pictures mysteriously would disappear.  So I had to remove the old page and insert the new.  Not very convenient. 

Will probably have more to add later...

Useful link to clone account

http://website-experts.ca/how-to-create-a-clone-button-on-accounts-in-salesforce/

Probably wouldn't need it everyday for most, but this is handy if I happen to need easy cloning in some special situations.