Plugin / Navigation help

I am using the following function that I coded (I am VERY new to this) to take the catgory page that someone is looking at to set a variable that I would like to use in my sidebar.

<?php
function myfunc(){
	global $myVar;
	if (is_category(16)) {
			$myVar = 16;
	}
	return $myVar;
}
?>

The only problem is that I think im using the code wrong in the sidebar.php

<?php
if (is_home()) {
        echo "<ul>";  wp_list_cats('optionall=0&sort_column=name&list=1&children=0');
        echo "</ul>";
} elseif (is_single() && $myCtg == "16") {
		echo "<ul>";	wp_list_bookmarks('category_before=<span>&category_after=</span>&categorize=1&category=16&show_images=0&show_description=0&orderby=url');
		echo "</ul>";
}
?>

because I also have an else set up to catch anything that doesnt work, and that is what keeps showing up in my sidebar.

Any ideas on how I could make this work, or am I going about this in an entirely wrong way?

Thanks