Legally or illegally, it's a tall order.  The only way you're going to get the price up in a hurry is by having access to at least a million dollars and buying up all the bids.

There have been various ideas floated before, such as asking sellers to retract their asks and 'force' bids upwards.  It never works.  If only one person doesn't cooperate and acts against the herd in their own interests then the entire manipulation fails.

The other question is, why does the value of a bitcoin have to go up?  It's just as useful at $3 as it is at $30.  If people are buying them up to speculate on the value rising in the future through sitting on their behinds and doing nothing, are they any better than the Wall Street 1%?