Instapaper has several (not offical, but good non the less) android clients:

https://market.android.com/details?id=com.codecarpet.reading... https://market.android.com/details?id=com.homelinux.hilo.eve....

there's only one readability client, which is not that good....

https://market.android.com/details?id=com.fahimk.readability....