Busen
"We're all Bozos on this bus." 
Under the bus.
( Eliza, busen is german for boobs. Just saying. )
Splunge
Mark
bye
money
Okay, if, like me, you saw this group of "associations" and went, "Huh?", at one point, I will tell you what I found out...
First, I assume Robin K had no idea what
single word to use in response to "under the bus", so he fell back on a Monty Python sketch, where a spineless corporate lackey replies, "splunge" when he couldn't think of anything else to say
(video clip here).
Next, we find LDW's response of "Mark", which, try as I might, I couldn't figure out.
Then, we come across Eliza's response of "bye", which meant even less to me. Having easier access to Eliza than to LDW, I asked her what the hell "bye" meant in reference to "Mark", and she told me "None, really." Apparently, she had originally replied to Robin's "splunge" with "Chapman" (referring to the late Graham Chapman, from the Python sketch, of course), but had included an explanation for Solvegas explaining that she was aware of what "busen" meant, but being American and not German, she associated that word with "bus", not breasts. She later received a PM from someone about her reply, and considered it an unfriendly dig (especially since it contained no smileys, apparently). Annoyed that what should be a pleasant game had turned somewhat sour, she removed her entire reply, but not before LDW posted "Mark" as his association for "Chapman". Eliza then withdrew from the game and posted "bye" in the typical fashion of a woman who is peeved.
"Was the PM really so nasty?" I asked her.
"No," she replied, "not at all. But it came across mean-spirited and so I'm done. I post there for fun and try to be nice. Once it's no longer fun, I'm done. So: 'bye'."
She would not tell me what the PM had said telling me that it wasn't all that bad, it had simply annoyed her. I shrugged my shoulders and looked at Haku's response to "bye", which was "money" and figured she associated "bye" with "buy", but also later realized that she's German, and thus, probably associated "Mark" with money much the same way a Briton would associate "pound", or an American "dollar".
That's my report, for what it's worth. And now... My turn at association, continuing with LDW's "Pink Floyd"...
Meat Grinder