Two-up icons in vertical panel bars?

Because I now have a high-resolution widescreen monitor, I keep all of my working icons in vertical panels on the left and right sides of my display to maximize the amount of vertical space for windows. I like to have my Preview & Pager applet set to two columns for easy switching between desktops, and that makes me want to use a Large size panel, but that means that I'm running out of space for application icons. Is there any way to make my icons appear two-up, the way the ones in the System Tray do? In the attached screenshot, both the right (main) panel and left panel are Large size. As can be seen, when the left panel is set to Large size, there's no more room for application icons. If the icons in the left panel could be displayed the way the ones in the System Tray appear, that would be very helpful. N.B. I don't like to use desktop icons, and I don't like using shortcut keys for switching desktops. Leslie