Don't listen to everyone saying there's no alternative, that's just stupid. Gmail works great for syncing up contacts, calendars, and Push email. Dropbox works for file storage.
+1
I used to use Google to sync up contacts and calendar. You do it by using the CalDAV accounts thing in iCal. It all worked over the air so I got OTA updates on my iPod touch without having to plug it into the computer.
It worked, although there were some rough edges. I always had trouble getting contacts to work right sometimes I would go in and find a lot of duplicates or even a few times missing entries. Calendars worked pretty well except for some reason I had trouble with iCal not being able to connect to the google account server from time to time. I had no such troubles with MM when I did the trial.
For bookmarks, I used Fruux (which can also do calendar and contact syncing but it won't do it OTA for a mobile device, only between full OSX computers).
It all worked, and was all free. Perfect? No. As seamless as MM? No. But I wasn't paying anything for it, so I tolerated the minor flaws. The only thing I didn't really get from it was iDisk, which I have determined to be nigh-useless for any kind of real cloud storage anyways. That and OTA bookmark syncing for my iPod touch.
I was finally convinced to get MM because I could get it less than the $100 asking price, and B2MM was something I found myself wanting to use more often. And I had been experiencing pretty constant google iCal syncing problems for about a month prior. I cobbled together a screen sharing solution for my needs, but the B2MM implementation is a lot nicer and if I read it right, just as secure as what I had going (I was doing an SSH tunnel to my computer using a pre-shared key authentication) already. The bonus is that I could turn off the remote login sharing service now and don't get exposed to random hacking attacks like I was before (confirmed by checking secure.log)
So basically I decided to pay some money to get rid of the rough edges in the free solutions I had going. As a bonus I get a me.com email address that has no ads, and I minimize my dissemination of personal information to the googles
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