[Annevecenqp]

This my dhikr regimen:

100 x Astaghfirullah al-Azim alladhi la ilaha illa huwa al-Hayyu l-Qayyum wa atubuh ilayh
Whoever says the above words, Allah will forgive him even if he deserted the army ranks. - Abu Dawud, Tirmidhi.

100 x Subhahallahi wa bihamdih
Sins are wiped away, even if they are like the foam of the sea, if this is repeated 100 times each day. - Bukhari, Muslim

At least 300 x durud upon the Prophet
The benefits of reciting blessings upon the Prophet are many: http://www.islam.co.za/khanka/virtues-durood.htm

In addition, there are certain duas that I like repeating:

Ya Hayyu Qayyumu birahmatika astagith
Allahummaghfirli, warhamni, wahdini, wa'afini, warzuqni
Allahummakfini bihalalika an haramik, wa aghnini bifadlika amman siwak
La ilaha illa anta subhanaka inni kuntu minazzalimin