A popular note-taking alternative is Evernote, which performs most of the same functions as Catch but requires an Evernote-specific account to function (free for individuals and $5 per user per month for companies). By contrast, an account on Catch is needed only if you want to enable syncing. Personally, I prefer the Catch interface, but both apps are excellent and fairly well matched in their capabilities.
Want to create a quick note to yourself without all the bells and whistles? Try Google's Voice Actions for Android, available free for any smartphone running Android 2.2 or higher. With Voice Actions, you can press and hold your smartphone's Search button and speak the words "note to self" followed by your message. Your smartphone will instantly transcribe the message and send it to you in an email.
If you're looking to make more traditional lists, Todoroo's Astrid Task/Todo List is a fine way to get the job done. Available as a free download, Astrid lets you create multiple to-do lists and check off tasks as you complete them. You can set individual task reminders, sync your tasks with Google Tasks, and automatically create new Google Calendar events for items as you add them. An optional $4 Power Pack gives you widgets, voice reminders, and other features.
Remember the Milk is another popular and full-featured list-making utility for Android. At its current cost, however -- $25 per year -- I can't recommend it; that price simply isn't competitive with other comparable options available for free or for one-time fees.
Databases DDH Software's $10 HanDBase Database Manager gives you the ability to create and edit work-oriented databases from your smartphone screen.
Glen Hughes's $3 Remote DB app enables SQL access from your Android device. It supports Microsoft SQL Server, MySQL, PostgreSQL, and Sybase database environments.