It's not like MS Office ... If it were like Excel, then I wouldn't find it incredibly awkward to use (Ctrl+D and Ctrl+R don't work, if you hit enter after tabbing over, it doesn't go back to the original column, etc.) ...
Anyways, if you're not used to Excel, it does the same thing (just not as easily). There's also Google Docs & Spreadsheets as well ...
openoffice is as close as your going to get to excel without paying for it //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif