13-inch laptop cases (clockwise from top left): Electric Guitar case, EQ case, TG Desk case and Desk Three case. The 'TG' design replicates the TG12345 recording desk (a Mk II and Mk III version are still in use today), 'Desk Three' is one of the studio's control room desks (behind the Abbey Road Studio 'clipping mask' effect text) and the 'EQ' pattern is, well... an EQ pattern.
The 'Electric Guitar' model features an upside down Stratocaster - the most famous left-handed player to flip a Strat over and play it this way is of course Mr James Marshall Hendrix. To the best of our knowledge, Jimi never actually recorded at Abbey Road, but the reference is unmistakeable. There's also a cool t-shirt featuring the same print.