Mangle the code above – should read:
<?php if (is_category('1')) : ?>
<?php $recent = new WP_Query("cat=1&showposts=12&offset=10"); while($recent->have_posts()) : $recent->the_post(); ?>
<a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
<?php endwhile; ?>
<?php elseif (is_category('2')) : ?>
<?php $recent = new WP_Query("cat=2&showposts=12&offset=10"); while($recent->have_posts()) : $recent->the_post(); ?>
<a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
<?php endwhile; ?>
...
<?php elseif (is_category('42')) : ?>
<?php $recent = new WP_Query("cat=42&showposts=12&offset=10"); while($recent->have_posts()) : $recent->the_post(); ?>
<a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
<?php endwhile; ?>
<?php endif; ?>