Ok, developers/dba's give it to me, I've always designed my database tables with a primary key of "Id", so i.e "Products" table will have a primary key column called "Id". However, I've seen other developers/dba's use "ProductId".
In general, I don't really care, however, since I'm a big fan of ActiveRecord and even before that I've always used "Id". Therefore, referencing my object is as easy as "Product.Id" rather than "Product.ProductId" - duplicate information! but my foreign key usually is "ProductId", so you'll see "OrderItems.ProductId" which makes sense to me. My "OrderItems" table will have a foreign key called "ProductId" back to the "Products.Id" column of the "Products" table.
Which method do you prefer?