Rainbow Dash's Played for LaughsHeroic B.S.O.D. when she realizes that the one lead she had - the Mare Do Well costume that Rarity sold - is completely worthless, because it was bought by Spike.
When taken out of context, the idea of Rainbow Dash sleeping in a bush is pretty funny. Not so much in context, as she's sleeping there because she can't get home due to her wings being broken.
"Ideally, she would have sprung forward only to have Rainbow Dash miraculously land in her outstretched forearms, bridal style, and then she could have carried her to safely. Instead there had been a lot more kicking, flailing limbs, and screaming of "Get away from me, you freak" during the actual catch, which hadn't been what she'd hoped for at all. She was lucky none of Rainbow Dash's hooves had made contact and knocked her unconscious. That would have just been ridiculous, to have made a comeback waking up unmasked in a hospital."
Mare Do Well in general tends to get some pretty funny lines - even though they mostly come at Rainbow Dash's expense, like when she makes fun of Dash for getting a wingboner.
Mare Do Well: I believe a less sophisticated pony would refer to it as a wingbo…but no. I am a classy mare, as you have undoubtedly picked up from my manner of speaking and dress. I won't stoop to such crude terminology, not for something as natural and beautiful as what your wings do when you're not paying attention.
When Rainbow Dash and Applejack get wasted at the Hearth's Warming Party, they end up having a rather interesting conversation.