No fuss Android + iOS + Mac setup
So I have a Samsung Galaxy S2 Skyrocket with CM10, an iPad Mini, and a MacBook Pro. Seems complicated, right? Not really. Everything just works... But wait, isn't that supposed to only apply to Apple products? Not really, and I'll show you some easy ways to make this setup work for you too.
iCloud in this case is only going to be useful for backups of our devices and documents, and of course for finding our lost devices from the web app. Plus, iMessage, if you do use it. So still set it up for the iPad/iPhone so you can get to your Pages/Day One, etc files.
Set up Google as your default account on Calendars & Reminders, and Notes in System Preferences. This way everything syncs back to Google Calendar and your GMail inbox. Your notes will be in a folder called Notes that you can access through the GMail app and possibly many other e-mail clients that have access to folders.
This way, you can still enjoy all the Apple default apps, but everything gets saved to your Google account. Reminders don't seem to work just yet with Google Tasks, but you have an iOS device anyway, so it's not a big deal. Just type them into the Calendar for now if you really need them on everything.
Syncing & Universal Apps
Syncing your Music & Videos - Most of us here like to use doubleTwist. The desktop app can take everything in your library, including iTunes U content and push it over to your device. All of the iTunes U content that isn't an iBook have no DRM on them, so you can easily open them up on your device with your reader of choice. If you pay the full price for everything, it works great with podcasts too. AirSync is pretty nice too. The interface is very iOS like too, which is why I personally like it.
Any.DO - This is a perfect Reminders replacement and it has apps for Android and iOS both. If you're already using Chrome as your desktop browser of choice, there's a web app for it too. The HTML5 version is supposed to be coming soon if you're a Safari user though.
For those that need an iPad friendly tasking app, Wunderlist and MobisleNotes (my personal favorite) also fit the bill.
Pushover Notifications - This can be used for numerous types of notifications. I personally use it with IFTTT for RSS feeds and the like. News Notifications on my Mac. You can also push stuff to your e-mail.
As for other things I use that are all universal... Evernote, Google Drive, Pocket, and AirDroid (so I don't have to use something like Kies to manage it).
And that's pretty much it. ~Ten minutes of your time to setup and never deal with it again. Dare I say it... It's probably easier than on a Windows based setup.