How can I make a vertical divider (like a horizontal rule) ?

HTML has a simple tag <hr> - the horizontal rule, which serves nicely as a quick divider for content.  However, often it's nice to separate columns using something like a "vertical rule".  However, that tag does not exist. 

The way I set up a vertical rule is using tables.  Now, tables are going out of fashion in favor of the <div> tag, but I don't care about that.  Face it, when you can't get a div to behave as you'd like, you fall back on the good old table. 

Anyway, here's my simple column style to get a vertical rule:

<td style="border-left:solid 2px #cfcfcf;">&nbsp;</td>

Now, you might need to use the "rowspan" parameter to have this carry down the whole page (or as far as you need).  The width and color are adjustable right there, or can be moved to a stylesheet easily.