Occasions like this tend to make people from all walks of life behave rather oddly. Take Jonathan Gillespie, for example. OMD's Mr Radio last week decided to inflict his own Elvis obsession on Capital Radio Group's sales and promotions department by setting them this rather eccentric challenge.
In an e-mail to Capital, Gillespie explained: "We are giving you all the opportunity to earn your OMD keep. No-one can take a booking from OMD or discuss future/ongoing business without singing a snippet of an Elvis song down the telephone."
For good measure, he added: "Love Me Tender is banned because I find it boring."
Well, Capital rose to the challenge admirably. For not only did the sales and promotion team serenade Gillespie all day with his favourite number, In the Ghetto, but the following morning they were waiting to entertain him in one of OMD's meeting rooms.
Capital's brand sales director, Mike Hope Milne, dressed as The King.
And the festivities continued when an Elvis song was dedicated to Gillespie during David Jensen's (remember him?) show on Capital Gold Networks.
Rumour has it that Gillespie has since taken to sitting around all day in spangly jumpsuits, popping pills and eating deep-fried chocolate cake while spouting red-neck filth at his entourage.