A combination of two wordpress caching plugins (Hyper Cache and Db Cachesignificantly improves the access times of a wordpress based blogs and websites.
Installing the two websites has drastically improved my blog opening times, so in my view having the two plugins on every wordpress install out there is a must! 
The plugins installation is straight forward, here is how I installed them.
1. Installing Hyper Cache on WordPress
To install Hyper Cache all I had to do is download and enable the plugin, the plugin doesn’t require any configuration. I always love it when I don’t have to bother with reading configuration options and pondering for some 20 minutes on the plugin features, so in that perspective Hyper Cache in my view is a good alternative to WordPress Super Cache
Besides that WordPress Super Cache was having issues when enabled on few wordpress based websites I manage these days. For comparison Hyper Cache worked just great on all wordpress install I tried the plugin so far.
To install all I had to do is download the plugin unzip and enable it:
a. Download and unzip it
debian:/var/www/blog# wget http://downloads.wordpress.org/plugin/hyper-cache.zip
...
debian:/var/www/blog# cd wp-content/plugins
debian:/var/www/blog/wp-content/plugins# unzip hyper-cache.zip
b. Enable Hyper Cache plugin
To enable the plugin follow to standard plugin location;
Plugins -> Inactive -> Hyper Cache (Enable)
To enable the plugin follow to standard plugin location;
Plugins -> Inactive -> Hyper Cache (Enable)
A mirror of current version of hyper-cache.zip plugin is here
2. Installing Wodpress Db Cache
What Db Cache, does it does caching of last queries made to MySQL for specified time, so if the query has to be refetched again from wordpress’s php frontend the queries results are fetched straight for the memory. This decreases the load towards the MySQL server and increases the webpages loading time.
As the plugin page suggests it’s way faster than other html caching-plugins like WP-Cache or WP Super Cache
However, I think its still slower than using a combination of WP Super Cache’s alternative Hyper Cache and Db Cache . Combining this two could rise the webpage opening times according to some statisticonline at best cases up to 830% !! 
Let me proceed with how I did the install of Db Cache .
a. Download and Install Db Cache
debian:/var/www/blog/wp-content/plugins# wget http://downloads.wordpress.org/plugin/db-cache.0.6.zip
...
debian:/var/www/blog/wp-content/plugins# unzip db-cache.0.6.zip
b. Enable the plugin
Plugins -> Inactive -> Db Cache (Enable)
c. Make sure the permissions for Db Cache are correct
On Debian to enable Db Cache, the permissions should be changed for Apache to have a read/write permissions to plugin directory, on Debian to fix the permissions I used the commands:
debian:/var/www/blog# chown www-data:www-data wp-content
debian:/var/www/blog# chown -R www-data:www-data wp-content/plugins/db-cache
On other GNU/Linux distributions the above commands (user and group) www-data:www-data, should be set to whatever user/group Apache is running with, on Slackware this would be nobody:nobody, on CentOS and RHEL it would be apache:apache.
Finally to enable Db Cache go to
Settings -> Db Cache -> (Tick Enable) -> Save