Either prescription or illegal, daily use of testosterone would not be cheap. On the other hand, if I am one of the people for whom testosterone works very well, it would be even more valuable than modafinil, in which case it is well worth even arduous experimenting. Since I am on the fence on whether it would help, this suggests the value of information is high.

…Phenethylamine is intrinsically a stimulant, although it doesn’t last long enough to express this property. In other words, it is rapidly and completely destroyed in the human body. It is only when a number of substituent groups are placed here or there on the molecule that this metabolic fate is avoided and pharmacological activity becomes apparent.
Another ingredient used in this formula is GABA or Gamma-Aminobutyric acid; it’s the second most common neurotransmitter found in the human brain. Being an inhibitory neurotransmitter it helps calm and reduce neuronal activity; this calming effect makes GABA an excellent ingredient in anti-anxiety medication. Lecithin is another ingredient found in Smart Pill and is a basic compound found in every cell of the body, with cardiovascular benefits it can also help restore the liver. Another effect is that it works with neurological functions such as memory or attention, thus improving brain Effectiveness.
Minnesota-based Medtronic offers a U.S. Food and Drug Administration (FDA)-cleared smart pill called PillCam COLON, which provides clear visualization of the colon and is complementary to colonoscopy. It is an alternative for patients who refuse invasive colon exams, have bleeding or sedation risks or inflammatory bowel disease, or have had a previous incomplete colonoscopy. PillCam COLON allows  more  people  to  get  screened  for  colorectal  cancer with  a  minimally  invasive, radiation-free option. The research focus for WCEs is on effective localization, steering and control of capsules. Device development relies on leveraging applied science and technologies for better system performance, rather than completely reengineering the pill.

Systematic reviews and meta-analyses of clinical human research using low doses of certain central nervous system stimulants found enhanced cognition in healthy people.[21][22][23] In particular, the classes of stimulants that demonstrate cognition-enhancing effects in humans act as direct agonists or indirect agonists of dopamine receptor D1, adrenoceptor A2, or both types of receptor in the prefrontal cortex.[21][22][24][25] Relatively high doses of stimulants cause cognitive deficits.[24][25]