CSS markup to make Tiny Tiny RSS look a bit more like Google Reader. Paste this into the Custom CSS box inside "Preferences".

custom.css

/* Reset
------------------------------------------------------------ */
body#ttrssMain,
body#ttrssPrefs,
body#ttrssLogin,
body {
    color: #000;
    font-family: "Arial", sans-serif;
    font-size: 100%; /* Set to default browser size, 16px */
    line-height: 1.5;
}


/* Folder Tree
------------------------------------------------------------ */
.dijitTreeContainer,
span.hlContent {
    font-size: 14px;
    font-size: 0.875rem; /* 14 / 16 */
}


/* Preview Pane
------------------------------------------------------------ */
.odd,
.even {
    background: #fff;
    padding: 5px;
    overflow: hidden;
}

.even.Unread,
.even.Unread td {
    background: #fff;
}

span.contentPreview,
span.author {
    display: none; /* I don't care for the content preview or author info. Just show me the headline */
}


/* Post Content
------------------------------------------------------------ */
div.postTitle a {
    color: #000;
    font-size: 20px;
    font-size: 1.250rem; /* 20 / 16 */
    font-weight: 700;
}

div.postReply div.postContent {
    font-size: 14px;
    font-size: 0.875rem; /* 14 / 16 */
    padding: 20px;
}

div.postContent p {
    margin-bottom: 16px;
    margin-bottom: 1rem; /* 16 / 16 */
}

Didn't work for me, maybe my fault.