Sudden/Unexpected DB Error, help please

Error:

WordPress database error: [Got error 28 from table handler]
SELECT * FROM wp_posts WHERE 1=1 AND (post_status = “publish” OR post_author = 1 AND post_status != ‘draft’ AND post_status != ‘static’) GROUP BY wp_posts.ID ORDER BY post_date DESC LIMIT 0, 15

I have been using 1.5 for quite some time, 1.2 before that. I made a post just now and suddenly my DB threw that error. My last backup is very old, sadly. Any tips guys?

Thanks