i can have even 4 spreadsheets open at once , one on each iMac g3 and one on the eMac and one on the monitor connected to the eMac and i can easy drag and drop things from one to the other as they are all within my network ,
so no problem there
i also can have 4 different websites open at once if i need to that is .
i can watch a film on fullscreen on the monitor while opening 2 websites and doing spreadsheets on the eMac and as my monitor is also a lcd tv i can watch tv while doing some cutting with final cut on the eMac and opening photoshop on one iMac g3 and looking ebay on the other iMac g3 .
so thats what i call multi tasking with fun
but i dont do anything apart from the spreadsheets and some other office staff for a living
i just prefer 4 smaller screens instead of one big one, and the + side of this setup is if one computer should fail for whatever reason the other 2 are still working

and another +, i have spare parts for all eventualities ready and it needs me only a hour to fix one of them
so if i would have a 27" iMac instead , if it breaks down for whatever reason i would have no computer at all,and dont say it wont happen ,just read the forum and you get a idea about the 27" iMacs reliability and because its under warranty i can not even fix it myself that would mean in the worst case just before a weekend no computer for 4 or more days