Giant (eg. Parkway Parade, next to Tampines IKEA, etc) has good
discount offers for several so-called portable aircons.
Because I have 3 PCs (one Windows XP, one Windows Vista, one
Windows 7, the latter two PCs using 32 inch LCD TVs as monitors,
and I connected both to the building antenna, so I can switch to TV
mode and watch two TV channels on two 32 inch LCD TVs in my room
simultaneously, but usually one will be TV mode, the other PC mode)
in my room generating a lot of heat, I have to install 3 air-cons
just for my room alone : 1 casement, 2 portable.

Oh, I also have a triple-fan in my room too (very hard to find
stock for such fans liao), both for use when the aircons are on (if
outside too hot, eg. hot afternoons, then 3 aircons + triple fan =
my very own Ice Cool Forest within blazing hot Singapore), and when
the aircons are off (when it's cooler in some nights, can switch
off aircons and just use fan).
You need to plan the positions of the portable aircons, because
each portable aircon will have two tubes out : hot air tube (that
goes out of window), and condenser tube (for which if you're
staying in an apartment like I am, you'll need to buy jerry-cans to
collect, and manually empty, the condensate water).
And yes, I'm paying the entire household's electricity bills. It's
not that expensive, as long as you switch off the aircons when you
leave the house (unlike all the multi-national corporate and
government office buildings).
Oh, I've a mini-fridge (the type found in hotel rooms) in my room
too. In the middle of the night, when thirsty, got ice-cold coke.
But sugary drinks can ruin your teeth, so be sure you rinse your
mouth after sugary drinks.
Better yet, brush your teeth with Novamin toothpastes (eg.
Sensodyne's Repair & Protect), which can actually re-mineralize
(ie. repair) teeth. All you guys reading this, once your teeth is
gone, it's gone forever. Better go buy Novamin toothpastes
today!