Ask HN: Here is my current batch of ideas. In exchange, I ask for your feedback.
I have a pool of unimplemented (or partially implemented) ideas laying around right now. I've decided to let them go into the wild in order to light a fire under myself to chase after which ever ones (if any) that I "miss" after I let go. Not claiming any of these are original, but I though there may be unique opportunities in some of them.

In sharing these, all I ask is that you provide feedback on them, even in the form of "I hate 1,2, don't care about 3, 5, 6, and I may be interested in 4."

1. An alternate twitter landing page (e.g. username.twitteridea.com) that each user can heavily style and customize. I'm shocked that Twitter customization is relegated to simple background images and color. Tweets are pulled via client-side javascript, so themes are simple html/css/js. As awful as MySpace skinning was, people clearly wanted it. Viral potential is large here. Main problem, people don't read a lot of tweets by visiting a user's profile. Revenue model a bit iffy.

2. A simplified system for conducting beta tests. Match up companies (thinking micro ISVs or small webapps here -- this is not an enterprise play) that need exposure + a diverse tester pool with people who like being early adopters. Allow testers to earn reputations and allow companies to filter candidates through quality thresholds. Now testers are incentivized to do a better job, so they can get into more "exclusive" betas. Plenty of room to add in social elements here too. I think someone must be doing this but I've yet to Google the right set of keywords to find them. The differentiator here is that it's an offering for testers too, not just companies. Almost creating a marketplace where the currency is reputation.

3. A hosted solution for referrals (non e-commerce - this is not an affiliate system). I posted about this here once at http://news.ycombinator.com/item?id=1280478. Basic idea is to host a system/api that lets you build per-user referral codes, track those referrals, and then provide widgets to let you give users badges, show top referrers, things like that.

4. A guided daily diary. Inspired by Keen's Simple Diary. http://www.simplediary.com Pose simple questions to allow people to reflect on each day. Short and sweet, no feeling of obligation. Okay, that's just a rehash of the book itself. Now make it interesting by crowd-sourcing the guided questions or making them social (amongst your friends). Share entries etc. Favoriting answers. This needs more fleshing out. Big problems are: content until you solve crowd-sourcing, and how to monetize.

5. Private blogs/microsocial sites for families. Keep it fun and easy - think Tumblr. #1 use case is just sharing photos - email sucks for this, nor am I friending grandma on Facebook to share photos, and almost all blogging platforms I've seen besides Posterous do not offer a reasonable password protection system. But after photo sharing, I think family member activity streams could be fun, and you could integrate some location functionality so kids could "check in" easily without having to call/txt etc. There are a lot of ways it could go. I posted about this at http://news.ycombinator.com/item?id=1385447. The offerings I can find - myfamily.com, familysays.com, and famiva.com are truly wretched. Seems like a huge opportunity here.

6. Site monitoring that goes beyond the simple "is it up"/ping/L7 health check junk. Gomez and Alertsite et al. are fine solutions but stupidly expensive. Just stupidly expensive. Seems like there is a gap you can slide into here between those two ends of the spectrum. Real admins measure their page latencies not just uptime. (Note: just found out about http://www.watchmouse.com today, which sort of moots this... seems to be just what I envisioned at the price point that I imagined could succeed.)