The following is a simple format of all world timezones:
<option value="-12">International Date Line (west) 04:08</option>
<option value="-11">Samoa 05:08</option>
<option value="-10">Hawaii 06:08</option>
<option value="-9">Alaska 07:08</option>
<option value="-8">Los Angeles 08:08</option>
<option value="-7">Denver 09:08</option>
<option value="-6">Chicago 10:08</option>
<option value="-5">New York 11:08</option>
<option value="-4">Caracas 13:08</option>
<option value="-3">Buenos Aires 13:08</option>
<option value="-2">Mid 14:08</option>
<option value="-1">Azores 15:08</option>
<option value="-0">London 16:08</option>
<option value="+1">Berlin, Madrid, Paris 17:08</option>
<option value="+2">Riga, Tallinn, Vilnius, Helsinki, Kiev, Minsk 18:08</option>
<option value="+3">Moscow, St. Petersburg, Volgograd 19:08</option>
<option value="+4">Samara, Baku, Yerevan 20:08</option>
<option value="+5">Yekaterinburg, Tashkent 21:08</option>
<option value="+6">Novosibirsk, Omsk 22:08</option>
<option value="+7">Krasnoyarsk, Bangkok 23:08</option>
<option value="+8">Irkutsk, Beijing 00:08</option>
<option value="+9">Chita, Yakutsk, Tokyo 01:08</option>
<option value="+10">Vladivostok, Sydney 02:08</option>
<option value="+11">Magadan, Sakhalin 03:08</option>
<option value="+12">Kamchatka 04:08</option>
<option value="+13">Tonga 05:08</option>
<option value="+14">Island Line 06:08</option>