exclude some posts from main page

Hi!

By default, all my posts are seen from main page and are sorted there in hronological order.

I want some of my posts (consisted some detailed technical info) to be not inluded into main page (i.e. not visible in “new posts”), but still visible form direct urls and serching (including tags and categories).

The first idea was to make them pages, but pages doesn’t have tags and categories and this is great disadvantage for me.
The second idea was to set some date in the past (for example, 1900 year), so all such posts will be at the end of main page and in fact not visible as “new” posts. But this hronological order remains also for search (including tags and categories) – this is also disadvantage for me.

So I want to modify some of my posts to make them not visible from main page, but retain all other functionality of posts ontouched.

Please, help me, how I can solve this problem?