The bookmarked poem by Pablo Neruda is "Mañana XXVII", the first line of which is "Desnuda, eres tan simple como una de tus manos". In English, that's "Naked, you are as simple as one of your hands". The rest of the poem describes features of his lover's naked body.
In Spell It 'M-A-N' (1993), While Doogie is on a date in his loft, his date references a time she was on a date and her date attempted (and failed) a 'Naked Man'.
Barney's comment about wanting to sleep with a very tall girl is a reference to the Seinfeld episode "The Boyfriend" (1992) in which George makes almost the exactly same comment.
Barney mentions that Mitch, the Naked Man, is like Superman. Guest star Courtney Ford is married to actor Brandon Routh, who played Superman in Superman Returns (2006).