I read this post:
and just had to check it out. On first glance,
this looks really cool. So, what's the catch?
I primarily use MS Office 2007, Macromedia products, Trillian, and Skype. Hypothetically, Portable Apps could replace all but Skype and Flash/Flex. (and I think Skype can be loaded onto a USB drive, but I've never tried it.)
What is the downside to this? Do the open source versions not work as well? Are they more vulnerable to attack? Is there a reason to pay for updating my current software to the latest versions?
First off, they aren't "open source versions." They are separate products that do the same jobs.
In many cases, the open source programs work better. They also tend to be more secure. Whether they work better for you is something you'll have to try for yourself.
Take Firefox. It is a full replacement for Internet Explorer. It has included tabbed browsing for YEARS - IE just got that with version 7. It is more compliant with web standards than IE - HOWEVER, sites buitl for IE (which has really crappy standards compliance) sometimes don't display properly with firefox. I prefer Firefox, but IE has its place as well. In a corporate environment, it is easier to centrally control IE. The basic program itself isn't as good or as secure as Firefox, but you can easily lock it down to prevent users from changing certain settings or doing particular things.
I also prefer OpenOffice over MS Office. MS Office has bugs that have irritated me since Word 97 came out. Things that just work under OO can cause grey hairs if you try them under MS Office. Large documents are also easier to work with under OO. MS Office tends to corrupt the files and go nuts if you get too much stuff in one file. OO stays stable.
On the other hand, MS Office has better spell checking, and OO doesn't have (that I know of) a grammar check. Then again, I can use OO in German (with German menus and text) then switch to English (with English menus and text.) OO includes dictionaries for multiple languages, and adding more is trivial. There's even a tool that will locate and install new language dictionaries and updates.
People who use Excel generally complan that OO Calc doesn't have pivot tables. If you need pivot tables, OO might not do for you. If you need a spreadsheet program that you can take with you, then Excel gets to be a problem. (I just checked. OO has pivot tables since version 2. something.)
The applications from Portableapps do not have to be installed on a USB stick. The open source programs are normal programs that can be installed on your PC. They are readily available for use on a USB stick because they are open source - any changes that need to be made to accomodate that use can be made to the program. Using MS Office from a USB stick would be a major pain. It can be done (I think) but the folks who do it have to play really nasty tricks on the operating system to do so - mostly they require that you install a special driver one the PC. Those folks charge bucks for their sneaky software. The PortableApps guys can give it away because it didn't cost them much to develop it in the first place. The applciations themselves they get from other projects - for free. The PortableApp software itself is free. Free+free=free.
All of the applications on the PortableApp site can be installed and used normally of your PC. You just download them from the original project site instead of the portable applications site.
Whether you want to (or must) continue paying money to Microsoft depends on what you do and with whom you must exchange files. And sometimes (surprise!) you do better in the exchange department when using open source software. Someone here created a booklet with MS Publisher and tried to have it printed by an offset print place. They only accept PDF files, which Publisher couldn't create. Scribus (an open source DTP program) does make PDF files, but it can't read MS Publisher files. Scribus also has very good support for PDF "pre-flight" checking, color profiles, and various other things that make life much easier when going to a printer. Making a simple PDF from a Publisher file is easy enough (more open source software, ghost script and ghostview,) but those files won't include the more advanced stuff - firstly because MS Pub hasn't got it and second because even it it did you couldn't get at it from outside.
Try the open source stuff. Use them on USB if you feel safer that way, but it will be slower. USB tends to be something of a bottleneck. If you like the programs, try installing them on your PC normally. If you don't like them, then just uninstall them and go back to using whatever it was before.