If the costs we're reasonable I would definitely rent scrypt/CPU hash power if I could somehow specify which coin and which pool at any given time I would mine.
I've made a good amount of BTC recently mining coins which hadn't hit exchanges at the time(easy mining/low difficulty) an then selling when they hit the exchanges with my measly ~2500k/hs mining PC. It could have been much more had I been able to increase my hashpower without having to upgrade my existing hardware.
Thank you for your feedback. Would you be able to tell us what coins you mined?
Sure, over the past 4-5 months I've mined pretty much each new scrypt and CPU coin upon release when the difficulty has been low and they're off exchange, sometimes I'll only mine for a day sometimes more depending on wether something new comes along, over time I've had particular success with COL, ADT, NET, TIX and more recently TAG.... I'm also holding relatively large numbers of ZEU, PPL, Skeincoin along with the sci-fi coins plus minor holdings of others such as Maples and Kudos in anticipation of them hitting exchanges. I currently have my scrypt hashes split between ZEU and TAG since they're both good coins and TAG is still relatively profitable ATM, my 24 g/hs ASIC is pointed at betacoin and both my CPUS are mining the newly released Datacoin.
It does have risks involved though since many coins don't/haven't hit exchanges but the potential profits of new coins at low difficulties offsets this risk IMO.
