And yes, that's a plurality as there are two inductees for August, both in keeping with our mini-salute to the Gallifreyan Time Lord known only as The Doctor from 'Doctor Who', and in a way also in keeping with the "dog days of August":
K-9 & THE TARDIS
As much as the tin dog has been reviled by some fans, K-9 has been one of the most popular of recurring characters on the show, and one of the longest-lasting companions for the Doctor. He's proven to be so popular, he's been spun off for his own adventures at least once so far, with the promise of an animated series soon to materialize.
But even though he is closely identified with the Doctor, it's K-9's association with Sarah Jane Smith that has helped to bring him into the "glory" of the TV Crossover Hall of Fame. After the Doctor had to leave Sarah Jane behind before returning to Gallfirey, he sent along K-9 to keep her company and to help her out of any future difficulties. Being a Time Lord, he may have already known what was to come for her; but he also knew that once you've gallivanted across the galaxy, it's hard to go back to a normal, uneventful life. So having K-9 along for protection certainly made more sense than a sonic lipstick.....
For more on K-9, see his entry at the TARDIS Wiki.
As for the TARDIS, the show would have been inconceivable without it! The Time And Relative Dimension In Space device has been revealed to be not just a machine, a conveyance, but a living creature, in much the same way Moya was a living spaceship on 'Farscape'.
Its distinctive shape in the form of a blue police box (caused by a malfunctioning and probably fused chameleon circuit) was instrumental in getting the Doctor himself into the Hall of Fame, as its appearance in shows like 'Red Dwarf' and 'Chelmsford 123' sell the assumption that if the TARDIS was there, the Doctor had to be as well. So it would be criminal not to recognize the TARDIS for its contributions.
Check out the page for the TARDIS at the TARDIS Wiki.
'Dimensions In Time'
'K-9 & Company'
'The Sarah Jane Adventures'
coming soon: 'K-9'
'Dimensions In Time'
THE CLASS OF 2007:
January - Johnny Carson `
February - Florence Johnston
March - Lou Grant
April - The Doctor
May - Sarah Jane Smith
June - Charlie Pace & Oceanic Airways
B'Day - Brigadier Alister Lethbridge-Stewart
July - Bret Maverick
August - K9 & TARDIS