On your body element's CSS, there is a webkit property;
-webkit-transform: rotate(-0.0000000001deg);
It is right here in your stylesheet on line 36:
http://www.generally.pl/style.php?id=4&lang=en
body {
/* Text-Sizing with ems: http://www.clagnut.com/blog/348/ */
font-family: Verdana, Helvetica, Arial, sans-serif;
color: #828282;
background-color: #FFFFFF;
/*font-size: 62.5%; This sets the default font size to be equivalent to 10px */
font-size: 10px;
margin: 0;
padding: 0;
-webkit-transform: rotate(-0.0000000001deg);
}
Unchecking this property in Chrome's inspector (F12) makes your scrollbar show up. My guess is that the original designer wanted to hide the scrollbar, so a very slight offset made it disappear. just comment out or delete this section and you will be fine.
Sorry I gave a quick answer earlier without actually trying it. I have deleted that post. This answer WILL work for Chrome. It should also work for Opera, though I don't have Opera installed on any of my computers. According to this Sitepoint article from May of last year, Opera implemented webkit extensions (but it doesn't list webkit-transform specifically):