On this question someone posted a link to an article arguing that Lazaraus is the beloved disciple. One of the arguments he makes is that his theory cleanly reconciles the account of a dinner in John 12 with the same account in Mark 14. In Mark 14:3, we see that the dinner is at the house of Simon the Leper. But it is less clear in John 12 where the dinner is. It says in 12:1 that "Jesus came to Bethany, where Lazarus lived, who Jesus had raised from the dead. Here a dinner was given in Jesus' honor." In English it seems ambiguous whether dinner was "where Lazarus lived" or whether it was merely in Bethany and "where Lazarus lived" only clarifies which Bethany. Is it also ambiguous in the Greek? Or does the Greek locate the dinner where Lazarus lives?
The greek is "βηθανιαν οπου ην λαζαρος" - which just means "Bethany, where Lazarus was".
As for the location of the dinner, the fact that Martha (Lazarus' sister) was serving suggests that it was at her house - which might have also been Lazarus' house.
The argument that Lazarus is the beloved disciple is interesting (particularly since he appears after Lazarus' life has been threatened), but the weight of scholars who actually try to name the beloved disciple still tend to choose John.